Page
NASA/SP-20210023927
NASA
Work Breakdown
Structure (WBS)
Handbook
November, 2021
National Aeronautics and
Space Administration
Electronic copies are available from:
NASA STI Program: http://www.sti.nasa.gov
NASA STI Information Desk
Email to: [email protected]/
(757) 864-9658
Write to:
NASA STI Information Desk
Mail Stop 148
NASA LaRC
Hampton, VA 23681-2199
OCFO-SID EVM Homepage
https://community.max.gov/display/NASA/
Earned+Value+Management+HOMEPAGE
(inside the NASA firewall only)
NASA Engineering Network (NEN)
Community Home Program/Project
Management
https://nen.nasa.gov/web/pm (inside the NASA
firewall only)
Page ii
TABLE OF CONTENTS
List of Figures and Illustrations.......................................................................................................v
Record of Revisions........................................................................................................................vi
Preface...........................................................................................................................................vii
P.1 Purpose...................................................................................................................................................................vii
P.2 Applicability...........................................................................................................................................................vii
P.3 References..............................................................................................................................................................vii
Chapter 1: Introduction.................................................................................................................viii
1.1 Background Information........................................................................................................................................viii
1.2 Policy.....................................................................................................................................................................viii
Chapter 2: WBS Overview..............................................................................................................9
2.1 Definition..................................................................................................................................................................9
2.2 WBS Hierarchy.......................................................................................................................................................10
2.2.1 Establishing and Maintaining WBS Codes in NASA’s Management Systems...................................................12
2.2.2 Contract Work Breakdown Structure (CWBS) and CWBS Dictionary...............................................................14
2.2.3 Work Breakdown Structure Elements by Other Performing Entities..................................................................16
2.3 Development Guidelines.........................................................................................................................................17
2.4 Summary.................................................................................................................................................................17
Chapter 3: WBS Development and Control...................................................................................19
3.1 WBS and the Project Life Cycle.............................................................................................................................19
3.2 WBS Activities and Responsibilities......................................................................................................................20
3.3 Development Considerations..................................................................................................................................22
3.3.1 Compatibility between WBS and CWBS............................................................................................................22
3.3.2 Compatibility with Internal Management Systems..............................................................................................23
3.3.3 Correlation with Other Requirements..................................................................................................................24
3.3.4 Number of Levels.................................................................................................................................................25
3.3.5 All Inclusiveness..................................................................................................................................................28
3.3.6 Change Control....................................................................................................................................................29
3.4 WBS Development Techniques..............................................................................................................................29
3.4.1 Preparing Functional Requirement Block Diagrams...........................................................................................29
3.4.2 Coding WBS Elements in a Consistent Manner..................................................................................................30
3.4.3 Preparing Element Tree Diagrams.......................................................................................................................31
3.4.4 Preparing a WBS Dictionary................................................................................................................................33
3.4.5 Using Development Checklists............................................................................................................................36
3.4.6 Using WBS Templates.........................................................................................................................................37
3.5 Common Development Errors................................................................................................................................38
3.5.1 Using Unsuitable Former WBS...........................................................................................................................38
3.5.2 Non-Product Elements.........................................................................................................................................38
3.5.3 Center Breakouts at Inappropriate Levels............................................................................................................39
3.5.4 Incorrect Element Hierarchy................................................................................................................................41
Chapter 4: WBS Uses....................................................................................................................43
4.1 Technical Management...........................................................................................................................................44
4.1.1 Specification Tree................................................................................................................................................44
4.1.2 Configuration Management.................................................................................................................................44
4.1.3 Integrated Logistics Support................................................................................................................................44
4.1.4 Test and Evaluation..............................................................................................................................................45
4.2 Work Identification and Assignment......................................................................................................................45
4.3 Schedule Management............................................................................................................................................46
4.4 Cost Management...................................................................................................................................................47
4.5 Performance Management......................................................................................................................................48
4.6 Risk Management...................................................................................................................................................49
NASA Work Breakdown Structure (WBS) Handbook Page iii
APPENDIX A: Acronym Listing..................................................................................................51
APPENDIX B: Glossary of Terms................................................................................................53
APPENDIX C: Standard Project WBS Level 2 Templates and WBS Dictionary Content
Descriptions...................................................................................................................................54
APPENDIX D: Standard Data Requirements Document (DRD)..................................................63
DATA REQUIREMENTS DESCRIPTION (DRD).....................................................................................................63
DRD Continuation Sheet..............................................................................................................................................65
15. DATA PREPARATION INFORMATION (CONTINUED):................................................................................65
APPENDIX E: Contractor CWBS Example..................................................................................66
NASA Work Breakdown Structure (WBS) Handbook Page iv
List of Figures and Illustrations
2-1 Project Development Cycles and Activities……………………………………………… 2
2-2 WBS Levels Illustration………………………………………………………….………..4
2-3 Partial WBS with Numbering System..…………………………………………………... 5
2-4 Illustration – WBS Code Request Template for Programs/Projects…….………………...7
2-5 Illustration – MdM Code Import Template………………………………………………. 7
2-6 WBS/CWBS Relationship………………………………………………………………... 9
3-1 WBS and the Project Life Cycle..………………………………………………………..12
3-2 WBS Product and Enabling Support Content…………………………….….…………..13
3-3 WBS Development Activities & Responsibilities..………………………….………….. 15
3-4 WBS Relational Interfaces to NASA Business/Management Systems…………………. 17
3-5 WBS Cross-Reference Matrix……………………………………………….………….. 18
3-6 WBS Hierarchy Illustration………………………………………………….………….. 19
3-7 Relationships between WBS, OBS, CA, WP, and PP……………………….………….. 21
3-8 Agency WBS Numbering System...…………………………………………………….. 22
3-9 Workaround for WBS Level 7 Limitations …………………….……..………………... 24
3-10 Partial WBS Tree Diagram Illustrating Recommended Practices……..………………... 25
3-11 Sample Software WBS Illustration……..………………………………………………..26
3-12 Example – WBS Index Excerpt………………………………………………................. 27
3-13 WBS Dictionary Example……………………………………………………..................29
3-14 WBS Checklist Example…………………………………………………………………30
3-15 Unsuitable Non-Product, Phase-Oriented WBS………………………………………… 32
3-16 Unsuitable Functional/Organizational Oriented WBS..……………………..…………...32
3-17 Center Breakout Guidance for a WBS…………………………………………………...34
3-18 Illustration of Incorrect Element Hierarchy……………………………………………...35
4-1 The WBS as a Project Management Tool for Integration…...…………………………...36
4-2 Responsibility Assignment Matrix (RAM)………………………………………………39
4-3 WBS and the Development of the Performance Measurement Baseline……………….. 42
4-4 WBS Serves as a Common Reference Point in Risk Management………………….….. 43
NASA Work Breakdown Structure (WBS) Handbook Page v
Record of Revisions
REV
LTR
DESCRIPTION DATE
Basic Issue January 2010
A Miscellaneous Minor Revisions October 2016
B Miscellaneous Minor Revisions January 2018
C Miscellaneous Minor Revisions September 2019
D
Miscellaneous Minor Revisions November 2021
NASA Work Breakdown Structure (WBS) Handbook Page vi
Preface
P.1 Purpose
The purpose of this document is to provide program/project teams necessary instruction and
guidance in the best practices for WBS and WBS dictionary development and use for project
implementation and management control. This handbook can be used for all types of NASA
projects and work activities including research, development, construction, test and evaluation,
and operations. The products of these work efforts may be hardware, software, data, or service
elements (alone or in combination). The aim of this document is to assist project teams in the
development of effective work breakdown structures that provide a framework of common
reference for all project elements.
The WBS and WBS dictionary are effective management processes for planning, organizing, and
administering NASA programs and projects. The guidance contained in this document is
applicable to both in-house, NASA-led effort and contracted effort. It assists management teams
from both entities in fulfilling necessary responsibilities for successful accomplishment of
project cost, schedule, and technical goals.
Benefits resulting from the use of an effective WBS include, but are not limited to: providing a
basis for assigned project responsibilities, providing a basis for project schedule and budget
development, simplifying a project by dividing the total work scope into manageable units, and
providing a common reference for all project communication.
P.2 Applicability
This handbook provides WBS and WBS dictionary development guidance for NASA
Headquarters, NASA Centers, the Jet Propulsion Laboratory, inter-government partners,
academic institutions, international partners, and contractors to the extent specified in the
contract or agreement.
P.3 References
NPD 7120.4, NASA Engineering and Program/Project Management Policy
NFS Part 1834, Major Systems Acquisition
Electronic Industries Alliance (EIA)-748,
Earned Value Management Systems Standard
NPR 7120.5, NASA Space Flight Program and Project Management Requirements
NPR 7120.7, NASA Information Technology Program and Project Mangement Requirements
NPR 7120.8, NASA Research and Technology Program and Project Management Requirements
MIL-STD-881, Department of Defense Standard Practice, Work Breakdown Structures for
Defense Materiel Items
PMI 978-1-933890-13-5, Practice Standard for Work Breakdown Structures
NASA Space Flight Program and Project Management Handbook
NASA Systems Engineering Handbook
NASA Work Breakdown Structure (WBS) Handbook Page vii
Chapter 1: Introduction
1.1 Background Information
In accordance with NFS Part 1834, Major Systems Acquisition, NASA policy NPD 7120.4,
NASA Engineering and Program/Project Management Policy, and directives NPR 7120.5, NASA
Space Flight Program and Project Management Requirements, NPR 7120.7, NASA Information
Technology Progam and Project Management Requirements, NPR 7120.8, NASA Research and
Technology Program and Project Management Requirements, the WBS and WBS Dictionary are
mandatory elements of a project’s management baseline. This section provides general WBS
information including policy, definition, guidelines, and development process.
1.2 Policy
Per NPR 7120.5, NPR 7120.7, NPR 7120.8, and NFS Part 1834, a project WBS is a key element
of NASA project management processes. The WBS and WBS Dictionary requirements
contained in these four documents apply to all types of NASA programs and projects depending
on the product line involved. The WBS is a core element of a project’s baseline throughout all
life cycle phases. It is the responsibility of each project manager and their project team to ensure
that the WBS requirements are adhered to, not only during initial WBS development, but also in
its on-going maintenance and control. The standard project WBS structures and templates
identified in the above NPRs were intended to apply only to new projects established on or after
June 1, 2005.
NASA Work Breakdown Structure (WBS) Handbook Page viii
Chapter 2: WBS Overview
2.1 Definition
Each NASA program has a set of goals which are developed from NASA mission needs. These
program goals are expanded into specific project objectives. The function of management is to plan
and direct project activities to achieve the program goals. The WBS is to be generated and utilized as a
key tool by management in order to execute the project/program.
A WBS is a product-oriented family tree that identifies the hardware, software, services, and all other
deliverables required to achieve an end project objective. The purpose of a WBS is to subdivide the
project’s work content into manageable segments to facilitate planning and control of cost, schedule,
and technical content. A WBS is developed early in the project development cycle as reflected below
within Figure 2-1. It identifies the total project work to be performed, which includes not only all
NASA in-house work content, but also all work content to be performed by contractors, international
partners, universities, or any other performing entities. Work scope not contained in the project WBS
should not be considered part of the project. The WBS divides the work content into manageable
elements, with increasing levels of detail.
Figure 2-1: Project Development Cycles and Activities
A WBS is developed by first identifying the system or project end item to be structured, and then
successively subdividing it into increasingly detailed and manageable subsidiary work products or
elements. Most of these elements are the direct result of work (e.g., assemblies, subassemblies, and
components), while others are simply the aggregation of selected products into logical sets (e.g.,
NASA Work Breakdown Structure (WBS) Handbook Page 9
buildings and utilities) for management control purposes. In either case, the subsidiary work product
has its own set of goals and objectives which must be met in order for the project objectives to be met.
Detailed tasks which must be performed to satisfy the subsidiary work product goals and objectives are
then identified and defined for each work product or element on which work will be performed.
Completion of an element is both measurable and verifiable based upon specific completion criteria
established during upfront project planning by the project team. Because WBS element/product
completion can be verified, a WBS provides a solid basis for technical, schedule, and cost plans and
status. No other structure (e.g., code of account, functional organization, budget and reporting, cost
element) satisfactorily provides an equally solid basis for incremental project performance assessment.
2.2 WBS Hierarchy
The project WBS structure should encompass the entire project’s approved scope of work. It usually
consists of multiple levels of products along with associated work content definitions that are contained
in a companion document called the WBS Dictionary. All NASA projects have the capability of
subdividing the work content down to any level necessary for management and insight. However, the
Agency’s Core Financial System currently limits the ability to capture costs to a maximum of seven
levels. These seven levels of the WBS are defined below.
• Level 1 is the entire project.
• Level 2 elements are the major operational product elements along with key common, enabling
products (as defined in NPR 7120.5, NPR 7120.7, and NPR 7120.8 standard WBS templates).
• Level 3-7 contains further definable subdivisions of the products contained in the level 2
elements (e.g., subsystems, components, documents, functionality).
There are numerous terms used to define level three and succeeding levels of the WBS below the
system level. Some typical examples used for hardware and software product elements are subsystem,
subassembly, component, module, functionality, equipment, and part. Project management and other
enabling organizational support products should use the subdivisions and terms that most effectively
and accurately depict the hierarchical breakdown of project work into meaningful products.
A properly structured WBS will readily allow complete aggregation of cost, schedule, and performance
data from lower elements up to the project or program level without allocation of a single element of
work scope to two or more WBS elements. WBS elements should be identified by a clear, descriptive
title and by a numbering scheme as defined by the project that performs the following functions:
• Identifies the level of the WBS element.
• Identifies the higher-level element into which the element will be integrated.
The following general illustration depicts how work scope can be arranged as hierarchical WBS levels
of work within a project. All project effort must be included, including all NASA in-house, contracted,
international partner, university, and any other performing entity implementations. Enabling
organizational common products must also be reflected appropriately with a project WBS (e.g., Project
Management, Safety & Management Assurance (S&MA), Systems Engineering and Integration
(SE&I)).
NASA Work Breakdown Structure (WBS) Handbook Page 10
Figure 2-2: WBS Levels Illustration
The following portion of a project WBS reflects an example of the NASA authorized WBS numbering
system. This numbering scheme is called the NASA Structure Management (NSM) system. For each
Agency project, the WBS established by the project team must use the NSM numbering scheme and
also must correlate exactly through level seven to the corresponding financial accounting structure
utilized for each project within the NASA Core Financial System. This requirement helps to ensure
that project costs are applied to the correct work scope being implemented by the project. This process
is necessary for carrying out successful Earned Value Management (EVM) processes.
NASA Work Breakdown Structure (WBS) Handbook Page 11
Figure 2-3: Partial WBS with Numbering System
The top two levels of a project WBS are dictated and controlled by the Agency through standard, level-
two WBS templates. These templates, along with their associated narrative content descriptions, are
contained in the NASA Special Publications, NPR 7120.5 and NPR 7120.8 (Appendix K for
Technology Development projects). WBS levels 3 and lower are developed and should be controlled
by project management and, as-required, prime contractors that are involved in project implementation.
In cases where prime contractors are involved, lower-level element coding must be traceable to the
appropriate upper-level elements that are controlled by the NASA Project Manager. While not being a
requirement, it is recommended that the prime contractor lower-level WBS numbering scheme be
consistent with the overall project WBS numbering format. This will allow easier total project
integration of cost and EVM data for project reporting.
NASA standard level-two WBS templates and narrative descriptions can be found in Appendix C.
2.2.1 Establishing and Maintaining WBS Codes in NASA’s Management Systems
All Programmatic and Institutional WBS element codes are not recognized as official NASA structures
until first being approved and established in the Agency’s Metadata Management (MdM) system. The
MdM system is a web-based enterprise application that contains the Agency’s official NSM data
NASA Work Breakdown Structure (WBS) Handbook Page 12
elements and associated attributes. MdM is the only Agency application used for identifying, creating,
tracking, organizing and archiving of Appropriation, Mission, Theme, Program, Project, and WBS 2
through 7 NSM structural elements. As the Agency’s enterprise repository for NSM data, MdM
supplies WBS codes to the Agency’s Core Financial System and the Budget Formulation System as
they require programmatic and hierarchical coding of data content. The WBS approval process
involves designated MdM code requesters/approvers that have been established across the Agency to
review new WBS elements requested by programmatic and institutional organizations. It should be
noted that project managers are not currently included as MdM code approvers. Because of this, all
project managers should continually monitor new WBS elements that are added to their projects for
validity and correctness.
Process instructions for entering new or modifying existing, WBS elements within the MdM system
may be obtained from the designated MdM code requester point of contact at each NASA Center.
Additional information regarding the MdM system may also be obtained by contacting the MdM Help
Desk ([email protected]). All modifications made to existing WBS element codes contained
in Agency management systems listed above must also first be initiated and approved through the MdM
System. A WBS code that has been approved and officially entered into the MdM System cannot be
removed. This restriction enhances a project’s ability to maintain accurate historical project data.
As a program/project or institutional organization determines the need, a code request may be
submitted to the authorized Center MdM code requester that addresses any of the following MdM
activity categories:
The creation of new WBS elements.
The modification of attribute data associated with any WBS element.
The total closure of a WBS element so that it is unavailable for any further Commitment,
Obligation, Cost, and Disbursement (COCD).
The “technical” closure of a WBS element so that it is unavailable for any further Commitments
and Obligations, but does allow availability for any final costs or disbursements for the element.
The “retirement” of WBS elements that are still in the Formulation structure and haven’t been
approved to receive funds.
The MdM code request involves the use of standard data templates. Figure 2-4 reflects an illustration
of just one example of a WBS code request template that may be used by program/project teams or
NASA institutional organizations. It should be understood that each NASA center will potentially have
a different code request template for use in submitting requests for new or modified WBS elements to
their authorized MdM code request point of contact. The center MdM code request point of contact will
then use an MdM import template (see Figure 2-5) to prepare requested data in the proper format for
review and import by the responsible MdM system office at NASA Headquarters. The request
templates aid in ensuring that all needed data is included and that the proper formatting is followed to
enable each request to be adequately reviewed, approved, and entered into the MdM system by the
authorized code requester.
NASA Work Breakdown Structure (WBS) Handbook Page 13
WBS Request Form PY06 & Forward
Submit Completed Form To:
MSFC-DL-WBSRequest
(Revised 12/01/2020)
A
(Add)
M (Modify)
TECO
(Technically Close)
WBS Level
(ex. WBS3,
WBS4, etc)
New WBS
Long Title
(40 Characters MAX)
Short Title
(20 Characters MAX)
Performing
Center
See Note #3
Below
Travel
(Y/N)
See Note #5
Below
Labor
(Y/N)
Procurement
(Y/N)
Capital Asset
Indicator (ACQ_EQ,
FAB_EQ, IUS,
THEME, REAL)
A WBS3 954879.01.04 Source Evaluation Panel HLS Source Eval Panel 01 N N N
A WBS4 954879.01.04.62 MSFC-Source Evaluation Panel MSFC-HLS SEP 62 N Y Y
The 2 lines above are
EXAMPLES
to add 954879.01.04 (WBS3) and 954879.01.04.62 (WBS4)……
Populate fields below as needed for your new code request … If you have questions, please contact Mark Denton @ (256)852-7828 or Leigh Fitzgerald @ (256)544-7269
Notes:
1. WBS Level column - use WBS3 vs. "3" and WBS4 vs. "4", etc
2. Title columns- Unless Agency, ALWAYS begin title with Center-Title (NO SPACES), ex. "MSFC-Avionics"
Please note character limits on titles above (20 for short title & 40 for long titles).
3. Performing Center - Use 2 digit Agency Installation Number (See list below):
01-Agency 51-GSFC
10-HQ 55-JPL
21-ARC 62-MSFC
22-GRC 64-SSC
23-LaRC 72-JSC
24-AFRC 76-KSC
99-NSSC
4. Submit Adds separate from Modify and TC.
ADVISE: Do not TECO for several months after use to allow all obligations are posted.
5. New codes will interface with CONCUR & WebTADS overnight after approved in MdM.
NEW projects that are activated for travel, will require a service request from the CFO Travel office to AAO in order to appear in CONCUR.
(Send travel activation request to MSFC-TravelOffice@mail.nasa.gov and include at least 2 fund certifiers.)
Codes are activated in WebTADS after WebTADS Date Forms are submitted and approved.
!
Figure 2-4: Illustration – WBS Code Request Template for Programs/Projects
Figure 2-5: Illustration – MdM Code Import Template
2.2.2 Contract Work Breakdown Structure (CWBS) and CWBS Dictionary
NASA Work Breakdown Structure (WBS) Handbook Page 14
For projects involving significant contracted effort, a project’s preliminary WBS should be included in
the Request for Proposal (RFP) and used as a starting point for individual contractors to develop their
extended CWBS. It is important to remember that each project will have only one WBS and that the
contractor’s CWBS is just an extension of the upper-level project WBS elements. The RFP will also
contain specific instructions to contractors that their proposal should be submitted in accordance with
the specified preliminary WBS. As noted in the previous section, the contractor’s WBS coding scheme
must be traceable to upper-level project controlled elements. Again, while not a requirement, it is
highly recommended that the extended CWBS be developed using a numbering format that is
consistent with or relatable to the standard NASA project WBS element numbering format.
The CWBS contains the complete WBS hierarchy for a specific contract scope of work. It is developed
by the contractor in accordance with the contract Statement of Work (SOW). It includes the WBS
elements for the products which are to be furnished by the contractor. The contractor extends these
elements and defines the lower-level products. It should be noted that within the contractor’s own
internal management systems and WBS process, there may not be the same limitation of a maximum of
seven levels within the product hierarchy, as is the case for NASA’s WBS hierarchical format.
However, as NASA projects reflect a total integrated WBS structure (containing both in-house and
contractor effort), only the upper-element levels of contractor products can typically be included due to
the seven-level limitation of the NSM numbering system. The contractor reporting requirements will
indicate the CWBS levels or elements for which contract status is to be reported to the government.
Contractor WBS reporting requirements are contained in a standard contractor Data Requirements
Document (DRD) which should be a part of the RFP. A standard DRD template is shown in Appendix
D.
A properly formulated CWBS provides a consistent and visible framework that facilitates uniform
planning, assignment of responsibilities, data summarization, and status reporting. A properly
formulated CWBS is also a key consideration in the successful implementation of EVM processes.
The following figure illustrates the relationship of an overall project WBS and its CWBS elements:
NASA Work Breakdown Structure (WBS) Handbook Page 15
WBS/CWBS Relationship
Project A
System A System B System C
Subsystem 1 Subsystem 2 Subsystem 3
WBS
CWBS
Contract X
Figure 2-6: WBS/CWBS Relationship
The following is a typical contract clause used for incorporating the CWBS into a contract. Project
managers should work with the contracts or procurement organization to develop the desired
contractual language for such a clause.
“A Contract Work Breakdown Structure has been negotiated between the government
and the contractor. The top levels of the Contract Work Breakdown Structure are
formally incorporated into the contract as set forth in Appendix E. The elements shown
in this exhibit may not be changed except by contractual action. Lower-tier elements
which are not shown in this exhibit may be changed by the contractor as appropriate,
provided that notification of such changes is provided to NASA’s Contracting Officer.”
A CWBS example is found in Appendix E.
2.2.3 Work Breakdown Structure Elements by Other Performing Entities
For projects involving scope content being implemented by other performing entities, such as (but not
limited to) international partners and universities, the WBS should also reflect this work content within
the overall hierarchy of project work. While other performing entities may, or may not have standard
contractual arrangements, they are nonetheless responsible for specified WBS elements through some
type of directed agreement arrangement with NASA. This work content must also be subdivided to an
appropriate level of product-oriented detail for project planning, control, and reporting. The resulting
work elements must be clearly identified and included within the project WBS under the correct
hierarchical branches in just the same manner as contractor CWBS elements. Again, while not a
NASA Work Breakdown Structure (WBS) Handbook Page 16
requirement, it is highly recommended that the extended WBS for other non-NASA work scope be
developed using a numbering format that is consistent with or relatable to the standard NASA WBS
element numbering format, or at a minimum clearly traceable to the correct upper-level WBS
hierarchical elements.
2.3 Development Guidelines
Only one WBS is prepared for each NASA project and includes both in-house and contractor effort.
While there is no single "right way" to prepare and utilize a WBS, there are some generally
recommended guidelines that should be followed. Considering the following general guidance will
assist in creating and implementing a WBS.
a. The WBS is prepared as early as project definition will permit.
b. A preliminary WBS is initially developed early in project formulation to define the top levels of
a WBS. These preliminary elements should reflect the entire scope of work contained in the
overall project life cycle including project definition, development, launch, and operations.
c. A single WBS is used for both technical and business management through level seven.
d. Both high level and detailed WBS planning should involve all stakeholders to ensure that proper
planning is done and that ALL parties agree on the final WBS prior to approval.
e. When a project is authorized by a Program Commitment Agreement (PCA), the WBS becomes
formalized as the project outline; changes to it must be formally approved by the program
office.
f. A preliminary CWBS is developed from the basic elements of the preliminary WBS and
expanded for use in the RFP, preparation of proposals, and the evaluation and selection process.
g. Normally, only the second or third level elements of the preliminary CWBS will be specified by
NASA in an RFP. The CWBS is considered a preliminary CWBS until it is finalized as a result
of negotiation and incorporated formally into the contract.
h. A total project WBS is created by combining the elements of the NASA in-house WBS
elements with the contractor’s CWBS elements, and also by all other WBS elements being
implemented by other performing entities.
i. As the project scope of work changes, the WBS is revised to reflect changes that are formally
approved through the configuration control process.
j. All top-level WBS elements do not have to be sub-divided to the same level of detail. As
associated element risk, cost, and/or complexity increases, further breakdown may be necessary.
k. When high-risk items are located at low CWBS levels (also low WBS levels by other performing
entities), these items can be identified against the higher-level WBS or CWBS element of which
the high risk item is a part.
While most project WBS structures are different at lower levels, the above guidance can help guarantee
that level one and two WBS elements are consistent across NASA projects. This ensures proper and
recommended WBS characteristics exist for all projects.
2.4 Summary
As previously discussed, a WBS defines all work to be performed for project completion. It is a
product-oriented structure, not an organizational structure. To develop and maintain a WBS, you must
have a clear understanding of the project's objectives and the end item(s) or end product(s) of the work
NASA Work Breakdown Structure (WBS) Handbook Page 17
to be performed. The WBS provides a common reference for all project communication, both
internally within the team and externally to project stakeholders. The WBS also provides a means of
rolling up project data to any desired level for analysis and oversight.
Because of its product orientation, a WBS provides the framework to plan, track and assess the project's
technical, schedule, and cost performance.
NASA Work Breakdown Structure (WBS) Handbook Page 18
Chapter 3: WBS Development and Control
3.1 WBS and the Project Life Cycle
A preliminary WBS is developed early in the conceptual stages of the project. It is established as soon
as program management believes the project has reached a stage of definition where it is feasible. It is
used to assist in the preparation of the PCA and the project plan. The preliminary project planning
process is an iterative process. During its early phases, the preliminary WBS may be revised as
necessary. Once the project is established with sufficient and stable scope definition, then both the
NASA in-house work elements and, if required, the CWBS elements can be adequately planned and
established at the necessary levels of detail.
CAUTION: Do not enter the full preliminary WBS into MdM system until the project’s definition of
work content has stabilized or until specific charge codes are needed for cost collection. The chart
below (Figure 3-1) reflects how the WBS development process relates to the project life cycle.
As early as Project definition will permit
FORMULATION PHASE IMPLEMENTATION PHASE
Major Decision Points
Pre-
Phase A:
Phase A: Phase B: Phase C: Phase D: Phase E:
Advanced
Studies
Preliminary
Analysis
Definition Design Development Operations
Preliminary WBS
Controlled Baseline WBS
(In-House/Contractor)
Source: APPL WBS Course
WBS and the Project Life Cycle
Baseline WBS Approval
KDP-C
Figure 3-1: WBS and the Project Life Cycle
Baseline approval of the WBS is achieved during the latter stages of project life-cycle phase “B”. Once
approved, the WBS should not be revised except through the formal approval process at major
NASA Work Breakdown Structure (WBS) Handbook Page 19
transitional points in the project.
3.2 WBS Activities and Responsibilities
The project manager is responsible for developing and maintaining the WBS and the WBS Dictionary.
This responsibility applies to WBS structures that are predominantly in-house NASA implemented
effort, contracted efforts requiring negotiation and approval of CWBS elements, and also to WBS
elements that are implemented by other performing entities.
The initial preliminary WBS may be developed as a totally new document based only on the
understanding of work scope at that time. Or a new WBS may also be developed from an existing
structure from a past similar project. The WBS evolves from an iterative analysis of:
a. Project objectives
b. Functional design criteria
c. Project scope
d. Technical performance requirements
e. Proposed methods of performance
f. Drawings, process flow charts, and other technical documentation
g. Risk and complexity (Note: Cost and schedule changes may impact scope which could drive
modifications to the WBS.)
As stated earlier, a project WBS, while being predominantly product-oriented, must also reflect all the
effort that is in the approved scope of work. Because of this, common elements of work must be
included that are not necessarily product-oriented. This effort is typically accomplished by “enabling
organizations,” such as project management, safety and mission assurance, etc. The chart below
(Figure 3-2) reflects how a project WBS contains both product-oriented elements and common
elements performed by enabling organizational support.
Figure 3-2: WBS Product and Enabling Support Content
The WBS should be developed by the project team and approved by the project manager. This
development must be a coordinated effort involving the following participants:
a. Systems Engineering
NASA Work Breakdown Structure (WBS) Handbook Page 20
b. Project Management
c. Business Management
d. Project Planning and Control (PP&C) Disciplines
e. Technical Disciplines
f. Safety & Mission Assurance
Projects with scopes of work to be implemented by predominantly in-house civil servants and
associated support contractors must also reflect their total effort with appropriate hierarchical
subdivided WBS elements. This subdivision of work must extend down to the point where work is
actually accomplished and charged.
The NASA project office incorporates a preliminary WBS into each RFP by selecting the appropriate
WBS elements for the work products that will be required by each contract. The WBS should be
accompanied by the initial WBS dictionary, which is a narrative definition of each element appearing
on the WBS. The RFP instructs potential contractors to extend the selected CWBS elements
appropriately.
Once NASA issues an RFP, the contractor extends the selected CWBS elements appropriately to create
a proposed CWBS to be submitted with the proposal. The RFP should also indicate the specified
format and content desired for the WBS Dictionary.
Contractors may suggest changes to selected CWBS elements when needed in order to meet an
essential requirement of the RFP or to enhance the effectiveness of the CWBS in satisfying the project
objectives. In preparing a contract proposal, a contractor may determine that the RFP requirements
pertaining to the CWBS would force some unusual requirements on existing contractor management
control systems. If this is the case, the contractor may request modifications to specific CWBS
requirements to minimize the impact on the contractor's existing management control systems.
As part of the proposal evaluation, a NASA team performs a technical and programmatic evaluation of
the CWBS submitted by each proposer. A contractor’s proposal may occasionally include alternate
technical approaches that impact the preliminary CWBS content contained in the RFP. In these cases,
NASA management must carefully evaluate the proposed CWBS changes and ensure the project
content is adequately addressed to successfully accomplish the contract objectives. Fortunately, the
procurement process provides specific opportunities for discussion and resolution of issues identified
within the proposal. Therefore, it is crucial that during these discussions, any exceptions taken by
NASA to a contractor’s proposed preliminary CWBS or CWBS Dictionary should be pointed out to the
contractor, so that an acceptable CWBS will be included with the contractor’s final proposal revision
and the resulting contract.
The contractor maintains the extended CWBS and CWBS Dictionary, including change traceability.
Only NASA-approved changes may be incorporated in accordance with the contract terms.
The following table (Figure 3-3) summarizes the WBS activities and identifies the responsible party for
each activity.
NASA Work Breakdown Structure (WBS) Handbook Page 21
Figure 3-3: WBS Development Activities & Responsibilities
3.3 Development Considerations
These items should be considered when developing a WBS or CWBS:
a. Compatibility between WBS and CWBS
b. Compatibility with internal management systems
c. Consistency with NASA Core Financial System
d. Correlation with other technical or programmatic requirements
e. Number of levels
f. All inclusiveness
g. Change control
h. Control Account (CA) levels for charging costs (for in-house NASA effort)
Following is a brief discussion of each consideration. Checklists to aid in the development process are
found in section 3.4.5 of Development Techniques.
3.3.1 Compatibility between WBS and CWBS
Each CWBS must be an extension of the WBS elements selected by NASA, and must be structured and
coded so that technical, schedule, and cost information may be readily summarized into the WBS.
There should be no work content included in any CWBS element that falls outside the defined work
content of the associated upper-level WBS element. In turn, the WBS must accommodate the
management and business systems’ needs of the performing contractors to a reasonable and practical
extent.
NASA Work Breakdown Structure (WBS) Handbook Page 22
In NASA’s current development and management environment, it is not unusual for projects to
establish a single extensive contract where the scope of work includes product content that crosses
multiple WBS elements. One example of this situation may involve a prime contractor with an
approved scope of work that entails development of hardware and/or software products for multiple
WBS system elements. Another example may involve a contract with a broad scope of work to supply
support contractors to assist government personnel in project work that leads to products in the
hierarchies of multiple WBS elements. In both of these cases, it is recommended that the contract
scope of work be subdivided in a product-oriented manner that allows for the most accurate depiction
of the hierarchical breakdown of project work into meaningful products. This means that a single
contract scope of work may entail multiple, clearly identifiable work products that require their
hierarchical positioning under multiple upper-level WBS elements. Proper structuring in this manner
will readily allow a more complete and meaningful aggregation of cost, schedule, and performance data
for management use. Please note that in these cases, it is imperative that the contracts are established
containing the necessary data requirements that will direct the contractors to submit incurred costs that
are clearly traceable to the correct CWBS elements where work was actually performed. It should also
be noted that correct cost reporting, as well as accurate and meaningful performance data are directly
dependent upon a clear, complete, and accurate WBS /CWBS hierarchy.
3.3.2 Compatibility with Internal Management Systems
The WBS is a tool used by NASA, contractor, and other non-NASA performing entities. Management
objectives and system capabilities play a significant role in the development of a WBS. NASA and
management from all other project performing entities have flexibility in developing a WBS to
accommodate their objectives and needs, which include effective and relational management and
reporting systems. It is critical to project success for the WBS to be structured and formatted in a
manner that is compatible with business/management system capabilities for budgeting, scheduling,
cost accounting, time keeping, and performance analysis. The WBS typically serves as the common
relational reference point between all these systems to allow for effective interface functionality (see
Figure 3-4). The ability for management systems to function as an integrated architecture is a key
ingredient to successful management processes.
NASA Work Breakdown Structure (WBS) Handbook Page 23
Figure 3-4: WBS Relational Interfaces to NASA Business/Management Systems
3.3.3 Correlation with Other Requirements
NASA and other non-NASA performing entities should give attention to the correlation of the WBS
with other requirements of the project, contract, and other applicable partnering agreements. Simply
stated, when developing the WBS, do not lose sight of the overall project (or contract/agreement) goals.
The WBS should represent the entire scope of work for the project. This should include all products
defined in the project’s authorized work scope. This also means that correlation must exist between
WBS content definition and all referenced requirement and specification documents. It is not
uncommon for the organization performing the systems engineering function to develop a functional
block diagram depicting the requirements per the NASA Systems Engineering Handbook (current
revision), and then correlate the diagram in developing a product-oriented WBS congruent with the
established templates located in NPR 7120.5 (Appendix H), NPR 7120.7, and NPR 7120.8 (Appendix
K). While not always necessary, it is useful for ensuring that all desired functionality is included.
Another very useful tool for WBS development is a cross-reference matrix (see Figure 3-5). This
matrix typically would have two axes: one horizontal and one vertical. Along one axis a reference to a
section or paragraph in the document or documents containing the product definition is listed. Along
the other axis the proposed WBS elements are listed. An “X” is then placed in the matrix at each
intersection of a requirement and a WBS element. A look across the matrix from the WBS element
perspective can quickly identify elements with no corresponding requirement. This condition would
indicate work that is not a part of the required scope and should be removed or formally added to the
NASA Work Breakdown Structure (WBS) Handbook Page 24
requirements. A look across the matrix from the requirements document or documents perspective will
indicate any areas where work scope has not been included in the WBS.
Figure 3-5: WBS Cross-Reference Matrix
3.3.4 Number of Levels
The hierarchical structure of a WBS is an important consideration. Project work is performed to satisfy
technical objectives established for each product or sub-product identified as a WBS element. As each
product is subdivided into greater depth within a WBS, each element’s technical complexity and
resource requirement are reduced. The number of levels and elements in the structure is generally
dependent upon the size and complexity of the total effort, the degree of technical uncertainty,
organizational structures concerned, and management’s judgment of need.
Figure 3-6 illustrates a hierarchical subdivision of work that is product oriented down to a level where
work is planned, costs are charged, and management insight is maintained.
NASA Work Breakdown Structure (WBS) Handbook Page 25
Figure 3-6: WBS Hierarchy Illustration
As the end product is decomposed into smaller sub-products at lower WBS levels, the work effort
required by each element can eventually be identified and relatable to an appropriate functional
organization. At some level on each WBS branch, management will assign responsibility for technical,
schedule, and cost performance. It is at this intersection of WBS element and organization unit that a
CA is usually established, work is scheduled, budget is planned, cost is collected, and performance is
measured, recorded and controlled. To do this, the technical content and requirements for each work
product must be clearly specified and documented. As project work is accomplished, actual completion
and technical requirements can be verified.
The WBS level at which a CA is established is primarily a function of the size of the project and the
type of product. The responsible organization level is a function of the management span of control
and upper management's desire to delegate technical, schedule, and cost responsibility for WBS
elements to lower management levels. It should be understood that all control accounts do not have to
be established at the same level within the WBS structure. A CA, if needed, may be subdivided further
into Work Packages (WPs) and Planning Packages (PPs). A WP provides further detail on work
content that is considered near-term, while a PP defines far-term work at a summary level. Each
product branch within the WBS only needs to be subdivided as far as needed to allow for adequate
management, insight, and control.
Control Account, Work Package, and Planning Package are terms typically associated with the
management process called EVM. Providing an EVM discussion is not the intent of this section.
However, due to many NASA projects requiring EVM implementation, and since there is such a close
and important relationship between the WBS, CA, WP, and PP, this topic will be addressed briefly. It
should be clearly understood by project teams involved in up-front project planning, that the quality and
NASA Work Breakdown Structure (WBS) Handbook Page 26
format of their WBS will correlate directly to how well they will be able to implement usable and
meaningful EVM practices.
A CA generally consists of one or more WPs and may include one or more PPs. A WP is the unit of
work required to complete a specific job such as a test, a report, a design, a set of drawings, fabrication
of a piece of hardware, or a service. A planning package is a logical aggregation of work within a CA
containing far-term effort which can be identified and budgeted in early baseline planning at a higher
level, but cannot yet be adequately defined into a WP. The WBS must be extended at a minimum to the
CA level, however, if lower insight is needed to enhance or satisfy management needs, then WPs or
PPs may be included within the WBS. If EVM is a project requirement, then careful early coordination
with the financial analyst is required to ensure that the WBS contains the needed levels of element
detail and that the correct WBS element codes are established as CA(s) and then activated within the
Agency’s Core Financial System to accept actual costs. This will enable the project to have the
capability to gather actual project costs at the necessary level of WBS detail to allow for meaningful
performance measurement.
Once the project content is hierarchically structured and defined in the manner described above, it is
then possible to satisfy the CA manager with specific data needs. Technical, schedule, and cost
information needed to effectively manage an organization's work can be easily supplied by the Center’s
management control systems by filtering to reflect only the appropriate WBS/CA element information.
Generally, the guidance provided in the above paragraphs will also apply to a contractor’s CWBS or
any other non-NASA performing entity’s WBS development process. As stated earlier in this
document, a contractor’s extended CWBS will normally begin at level three or four. Additional levels
of sub-division may be included prior to starting the CWBS when it is necessary to more clearly
communicate all project requirements, or if there is a significant degree of technical risk or complexity.
Prime contractors, as well as other non-NASA performing entities should also extend their hierarchical
elements in a predominantly product-oriented fashion. The RFP/agreement should instruct all
performing entities to extend their CWBS/WBS elements to a level as low as necessary to provide
meaningful CA planning, insight, and control.
The following illustration (Figure 3-7) shows how CA(s) fit into the overall project management
process.
NASA Work Breakdown Structure (WBS) Handbook Page 27
Figure 3-7: Relationships between WBS, OBS, CA, WP, and PP
When identifying CAs, the performing entities must be allowed to establish organizational
responsibilities at meaningful and appropriate levels. The CA brings together all aspects of the
management control systems, including technical definition, budgets, estimates, schedules, work
assignments, accounting, progress assessment, risk and problem identification, and associated
corrective actions.
3.3.5 All Inclusiveness
A WBS should include all NASA in-house, contracted, and other non-NASA performing entity work
and products defined in the project scope of work. The WBS should never contain unauthorized work
scope.
Major subcontracts, if any, will also need to be included. In some cases, the subcontracted effort may
provide for delivery of a single lower-level CWBS element, such as a vendor-fabricated subassembly.
In other cases, the subcontract may provide for effort covering several lower-level CWBS elements,
such as design for the electronics, communications, and instrumentation systems in a new facility. In
either case, the prime contractor's CWBS dictionary (and other management control systems) must be
capable of uniquely distinguishing major subcontractors' responsibilities from each other and from the
work retained in-house by the prime contractor. This is accomplished at the lower levels of the CWBS.
NASA Work Breakdown Structure (WBS) Handbook Page 28
3.3.6 Change Control
WBS development is an iterative process. While strong efforts should be placed on early and accurate
WBS planning, after a baseline is established, WBS revisions will likely still occur from expansion or
contraction of project or contract scope, and the movement of a project through its various stages (e.g.,
engineering, development, and operation). Whenever the baseline WBS is revised, whether it be in-
house NASA elements or contractor elements, formal documentation of the revision must be
maintained according to the project’s configuration and data management process to include the
associated change rationale and project manager approval.
Changes may occur as the products of the work effort are more accurately defined or when a revised
product structure (resulting from technically different requirements or a more cost effective approach to
satisfy the requirements) is used. The WBS and WBS Dictionary should also be revised to reflect
changes resulting from contract negotiations.
The extended CWBS is a contractual requirement and specified portions may not be changed without
NASA approval. The contract should specify the CWBS elements for which NASA approval is
required prior to contractor revision. Usually, the NASA controlled elements are identical to those
specified for periodic contractor reporting. Approval of contractor proposed changes to the
WBS/CWBS must be made with great care. It is important to always maintain the ability within the
overall WBS to identify the interrelationships of each contractor's efforts to the overall project
objectives.
A disciplined WBS change control process, as described above for NASA in-house and contracted
effort, should also be applied in similar fashion to all other project non-NASA performing entities.
Each project manager is ultimately responsible for establishing and controlling the approved WBS
baseline. Project personnel should aid the project manager in this regard by routine monitoring of the
WBS codes and associated attribute data contained in the MdM System and other Agency management
systems. Monitoring activity should include the review for new, modified, and closed WBS element
codes that have been entered into the MdM System without the approval of the project manager.
3.4 WBS Development Techniques
The following techniques can be helpful in the development of a project WBS:
a. Preparing functional requirement block diagrams
b. Coding WBS elements in a consistent manner
c. Preparing element tree diagrams
d. Preparing a WBS dictionary
e. Using development checklists
f. Using WBS templates
3.4.1 Preparing Functional Requirement Block Diagrams
A good place to begin developing a preliminary WBS is by listing the functional requirements for the
new product or system. If the number of requirements is large, group them into similar categories.
Create a parent or end product at the top of your list or graphic. Then, create subordinate major
groupings of functional requirements with similar characteristics. Next, subdivide the major groupings
NASA Work Breakdown Structure (WBS) Handbook Page 29
into smaller groupings that have natural dividing points. Finally, translate this functional block diagram
into a product structure.
In order to translate the functional block diagram into a product structure, begin at the top level with the
desired end product that is completely integrated. At the first subordinate level, using the functional
block diagram, create a major system block for each related functional block or blocks. The translation
may result in a one-to-one, one-to-many, or many-to-one relationship between the functional blocks
and the major system blocks. Create subsystem or other subordinate blocks that further define the
major system blocks as necessary. Continue this process until the product structure is complete and all
functional requirements are accounted for. The result is your initial WBS.
3.4.2 Coding WBS Elements in a Consistent Manner
The NSM System is the internal coding system used by the Agency to define and organize project work
content. This same coding system is also used to account for all financial activities associated with
funds appropriated by Congress to accomplish project work. When developing a project WBS, the
management team coordinates with the financial organization to establish a WBS coding structure that
will not only work for technical management of the effort, but also consistently matches the coding
structure used by the NASA financial community for cost accounting.
Each WBS element is assigned a unique element code to be used as a reference point for its technical
and financial identification throughout the life of the project. A simple decimal coding system that
logically indicates the level of an element and related lower-level subordinate elements is applied. A
common coding nomenclature facilitates communications among all project participants. Each CWBS,
or other non-NASA performing entity WBS coding arrangement, must be traceable to the NASA WBS
coding system. The NSM coding structure is illustrated below.
NASA Work Breakdown Structure (WBS) Handbook Page 30
Figure 3-8: Agency WBS Numbering System
As illustrated above, each NASA Project (Level 1) is assigned a six-digit numeric code such as 123456.
Each sub-level code contains a two-digit numeric code separated from the previous level code by a
period. Level 2 codes would appear as 123456.02 and Level 4 codes would look like 123456.02.07.05.
A maximum of seven levels is allowed in the WBS coding structure contained in the Agency Core
Financial System. The typical lowest level might appear as 123456.02.07.05.02.06.03 containing a
maximum of 24 characters including all the periods.
In projects that need to expand the WBS below level 7 in the Core Financial System to manage the
work and collect costs, a workaround has been identified. In this workaround, the WBS in the Core
Financial System will stay the same down to level 7 and additional elements will be added horizontally
at level 7 of the WBS to collect costs. These costs are then mapped to the appropriate lower-level WBS
in the COTS cost tools. For more information for this workaround contact your organizational EVM
Focal Point.
Figure 3-9: Workaround for WBS Level 7 Limitations
3.4.3 Preparing Element Tree Diagrams
WBS tree diagrams are routinely developed to provide a visual display of a WBS. A pictorial view of
the overall WBS aids all project staff in understanding how lower-level project components support and
contribute to higher-level components. This type of diagram is often called a "family tree" or a
“product tree” diagram.
NASA Work Breakdown Structure (WBS) Handbook Page 31
"#"#
$!
WBS in Cobra & SAP
Examples of WBS tree diagrams are shown below. The first illustration, Figure 3-10, reflects a portion
of a Flight Project WBS structure with several key recommended development practices noted. The
second illustration, Figure 3-11, portrays a sample portion of a Software Development Project WBS
that focuses on software products sub-divided by their functionality.
Partial Project WBS Element Tree Diagram
(Recommended WBS Development Practices Highlighted)
Incl. Common
Elements by
Enabling Orgs
Product Oriented
Standard
Level 2’s
Clear WBS Titles
Center Breakout at
Lowest Level of Sub-
division
Top Down
Development
Figure 3-10: Partial WBS Tree Diagram Illustrating Recommended Practices
NASA Work Breakdown Structure (WBS) Handbook Page 32
Figure 3-11: Sample Software WBS Illustration
3.4.4 Preparing a WBS Dictionary
A WBS dictionary lists and defines the WBS element contents. It is prepared by the project team for
the purposes of ensuring that all work scope has been identified and to eliminate duplication and
overlap of work assignments. Content ambiguities should be eliminated with clear statements
describing the effort to be completed. The level of descriptive detail needed for each element should be
commensurate with the element’s hierarchical position in the overall WBS structure. The lower the
level of a WBS element, the greater the level of descriptive detail needed. The descriptive detail of
element content should clearly identify all element interfaces. The WBS Dictionary is expanded in
greater detail for those extended levels established by contractors as the CWBS is developed. Other
non-NASA project performing entities will also develop and expand their WBS Dictionary descriptive
content in the same fashion as noted above for contractors.
The WBS dictionary element content descriptions should be clear enough to assist in providing a link to
the detailed technical documents. The dictionary also contains an index (see Figure 3-12) which lists
the WBS elements in indented format to show their hierarchical relationship.
NASA Work Breakdown Structure (WBS) Handbook Page 33
Figure 3-12: Example - WBS Index Excerpt
Each element definition should include the following:
a. WBS element title
b. WBS element code
c. WBS element content description (including quantities, relevant associated work, and contract
end items where applicable)
d. WBS Index
e. Scope definition paragraph number
f. Specification (number and title) associated with the WBS element (if applicable)
NASA Work Breakdown Structure (WBS) Handbook Page 34
g. Date, revision number, revision authorization and approved changes
h. Budget and reporting number (i.e., Charge Code)
Contract WBS Dictionary should include all the above as well as the following:
i. Contract line item associated with the WBS element
j. Contract Identification Number
A WBS dictionary (Figure 3-13) should be a controlled document, and as such, should be maintained as
a baseline document with revisions being reviewed and approved according to each project’s
configuration control requirements for the life of the project.
NASA Work Breakdown Structure (WBS) Handbook Page 35
Figure 3-13: WBS Dictionary Example
3.4.5 Using Development Checklists
Checklists are a useful tool to ensure proper WBS development. A WBS checklist helps ensure that all
major factors have been considered. Consider the following checklist example (Figure 3-14):
NASA Work Breakdown Structure (WBS) Handbook Page 36
Figure 3-14: WBS Checklist Example
3.4.6 Using WBS Templates
Since the purpose of a WBS is to divide the project into manageable pieces of work for better planning
and control, it only makes sense to add more consistency to this process through the use of standard
WBS templates. This standardization not only aids in sub-dividing the work in current projects, but
NASA Work Breakdown Structure (WBS) Handbook Page 37
will also make possible the creation of historical data repositories of cost, schedule, and technical
information with standard content categories to aid in the planning of future projects. Standard WBS
templates are intended to apply to projects, not programs. There are no program WBS standard
requirements due to the variance in structure of the Mission Directorates.
As noted earlier, the top two levels of a project WBS are dictated and controlled by the Agency through
standard templates. These templates, along with their associated narrative content descriptions, are
contained in NPR 7120.5 (Appendix H), NASA Space Flight Program and Project Management
Handbook (current revision – section 5.9.1), NPR 7120.7, and NPR 7120.8 (Appendix K). These
Agency templates are also found in Appendix C of this document. WBS levels 3 and lower are
developed and controlled by project management and, as required, prime contractors that are involved
in project implementation.
3.5 Common Development Errors
Developing a properly structured and effective project WBS is a complex process. Increased training in
the “best practices” for effective WBS development will help reduce the errors that are commonly
found. Examples of common WBS development errors are illustrated in the following paragraphs.
3.5.1 Using Unsuitable Former WBS
If a WBS from a prior project is used as a basis for WBS development on a new project or contract, be
careful not to perpetuate any mistakes or undesirable features of the earlier WBS.
3.5.2 Non-Product Elements
WBS elements should be predominantly product oriented. For example, Design, Engineering,
Manufacturing, Phase A, Pipe Fitters, and Direct Labor are not products and typically should not be
used for WBS element sub-divisions. Design, Engineering, and Manufacturing are functions and/or
organizations, and Pipe Fitter is a skill type, Direct Labor is a labor category, and Phase A is a time
frame. None are appropriate as WBS elements. Rework, Retesting and Refurbishing are additional
non-product oriented terms and are not usually recommended as appropriate for WBS element
hierarchy.
There is a natural tendency for project managers and contractors to ask, “Where am I in that WBS?”
They feel more comfortable if they see specific elements which reflect their functional or organizational
areas of responsibility. Since projects many times are functionally organized, the tendency may be for
a project team to approve a functionally- or organizationally-oriented WBS. This error should be
avoided. The figures below (Figure 3-15 and 3-16) illustrate typical non-product oriented errors.
NASA Work Breakdown Structure (WBS) Handbook Page 38
Management
Project X
This Approach is Not Recommended
Phase C Dev
Level 2 Elements are Phase
Oriented
(No Clarity on Scope Definition or Products to be Developed)
Phase C Dev
Phase C Dev
Figure 3-15: Unsuitable Non-Product, Phase-Oriented WBS
Management
Project X
This Approach is Not Recommended
Test &
Verification
Level 2 Elements are
Function/Organizational
Oriented
(No Clarity on Scope Definition or Products to be Developed)
Engineering
Fabrication
Figure 3-16: Unsuitable Function/Organizational Oriented WBS
3.5.3 Center Breakouts at Inappropriate Levels
NASA projects commonly have involvement from multiple Centers. Current Agency accounting
requirements dictate that all Centers with responsibilities for implementing selected portions of work
scope within a project must be uniquely identified within the project WBS. Caution must be exercised
when including these ‘other Center’ work elements within the WBS. A common error in developing a
project WBS with multiple Center involvement is to insert the Center element at too high a level of the
WBS and not at the lower level where work is actually being planned and accomplished. It should be
NASA Work Breakdown Structure (WBS) Handbook Page 39
structured in a manner that includes Center-designated elements at the lowest level needed where time
is actually charged and costs are collected (not necessarily the seventh level). The reason for this
recommendation is to prevent work elements from being fragmented at too high a level. This prevents
automated data roll-up and breakdown capabilities that capture the total hardware system development
costs and performance for specific system hardware. This error also results in wasted levels of the
project WBS so that there may not be enough levels remaining to adequately subdivide the work scope.
It should be noted that with only seven WBS levels available within the NSM and financial accounting
systems, the project team must use them wisely. The following example (Figure 3-17) illustrates this
common error.
NASA Work Breakdown Structure (WBS) Handbook Page 40
Figure 3-17: Center Breakout Guidance for a WBS
3.5.4 Incorrect Element Hierarchy
A common error in WBS development is sub-dividing the elements in a manner that doesn’t correctly
reflect the hierarchy of work structure. This error many times is due to not having the right personnel
involved in the WBS development effort. A lack of understanding of the total work scope, system
hardware, and the implementation processes make it nearly impossible to correctly build a WBS
NASA Work Breakdown Structure (WBS) Handbook Page 41
without the responsible and knowledgeable people involved. The simple example below (Figure 3-18)
illustrates an incorrect sub-division of work elements.
Incorrect Element
Hierarchy
Yes
Transmitter Amplifier
Subsystem A
No
Amplifier
Transmitter
Subsystem A
Correct Element
Hierarchy
Amplifier is NOT a Sub-Element of
Transmitter, but Rather a Co-Element
Breakdown of Subsystem “A”
Figure 3-18: Illustration of Incorrect Element Hierarchy
NASA Work Breakdown Structure (WBS) Handbook Page 42
Chapter 4: WBS Uses
The WBS is a project management tool. It provides a framework for specifying the technical aspects of
the project by defining the project in terms of hierarchically-related, product-oriented elements for the
total project scope of work. The WBS also provides the framework for schedule and budget
development. As a common framework for cost, schedule, and technical management, the WBS
elements serve as logical summary points for insight and assessment of measuring cost and schedule
performance. Figure 4-1, shown below, illustrates how the WBS provides a common reference
capability in relating cost, schedule, and technical data.
Figure 4-1: The WBS as a Project Management Tool for Integration
The following paragraphs discuss using the WBS for:
a. Technical Management
b. Work Identification and Assignment
c. Schedule Management
d. Cost Management
NASA Work Breakdown Structure (WBS) Handbook Page 43
e. Performance Management
f. Risk Management
4.1 Technical Management
The WBS provides the framework for defining the technical objectives, establishing a specification
tree, defining configuration items, providing Integrated Logistic Support (ILS), and preparing and
executing a test and evaluation plan for a project.
4.1.1 Specification Tree
A specification tree, developed by system engineering, structures the performance parameters for the
system or systems being developed. It subdivides the system(s) into its functional constituent elements
and identifies the performance objectives of the system(s) and its elements. The performance
characteristics are explicitly identified and quantified. The completed specification tree represents a
hierarchy of performance requirements for each element of the system for which design responsibility
is assigned. Because specifications may not be written for each WBS element, the specification tree
may not map to the entire WBS structure.
Technical specification tree development is a sub-element of the standard level two “Systems
Engineering” WBS element.
4.1.2 Configuration Management
Configuration Management (CM) includes the process of managing the technical configuration of
elements being developed. In establishing the requirement for project configuration management, each
project office designates which technical documents and deliverables are subject to CM controls.
A technical document and/or contract deliverable designated for CM is called a configuration item.
CM involves defining the baseline configuration for the configuration items, controlling the changes to
that baseline, accounting for all approved changes, and verifying that all changes have occurred. The
WBS is the framework for designating the configuration items on a project. Thus, the WBS needs to be
extended sufficiently to clearly define all elements subject to configuration management.
CM effort should be a sub-element of the standard level two “Systems Engineering” WBS element.
4.1.3 Integrated Logistics Support
ILS includes all support necessary to assure the effective and economical support of a project, system,
or equipment for the project's life cycle. ILS efforts include:
a. Spare and repair parts inventories, warehousing, and control
b. Preventive and scheduled facilities and equipment maintenance
c. Reliability and maintainability data
d. Transportation and handling systems
e. Test equipment
f. Training
g. Related publications
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ILS efforts require detailed definitions of the systems or components being supported down to the
individual spare part or individual component receiving preventive maintenance. The WBS provides a
hierarchical basis for such detailed definition.
ILS effort should be a sub-element of the standard level two “Systems Engineering” WBS element.
4.1.4 Test and Evaluation
Many projects require a formal test and evaluation plan to ensure the acquired element products satisfy
the project's objectives as defined by the project technical baselines. Test plans may be developed for
individual WBS elements. The effort associated with conducting and evaluating those tests may
become part of the work defined for the appropriate WBS element.
Since tests may involve entire systems, parts of systems or individual components, they may not be
uniquely identifiable to a single WBS element, but may be included in two or more of the elements
going into one higher-level WBS element. Such integrated test work may be planned in conjunction
with other work on the higher-level element that incorporates the elements being tested. Lower-level
component or sub-assembly test effort may be established as sub-elements under the associated upper-
level hardware WBS element for planning and controlling all tests.
Integrated testing of the project’s completed, overall level two systems (e.g. payloads,
aircraft/spacecraft, and launch vehicle/services) should be established as sub-elements of the standard
level two “Systems Integration and Testing” WBS element. This includes both procured and NASA
developed element products.
4.2 Work Identification and Assignment
People performing work are organized to facilitate effective management, whether the organization is
designed along project, functional, or matrix lines. To assign specific work responsibility to a specific
organization, the WBS and organizational structure should be integrated with each other (i.e.,
functional responsibility is established for managing specified work to produce defined products). This
integration process results in a Responsibility Assignment Matrix (RAM) which is illustrated below in
Figure 4-2. This integration can occur at any level of the WBS and at whatever level of responsibility
has been assigned to manage the work. While an interface relationship may exist between the
organizational structure and the WBS keep in mind that the organizational structure should not drive
how the WBS is structured and sub-divided. The WBS hierarchy should be driven totally by the
makeup of the work content and how it can most effectively be sub-divided for management planning,
insight, and control.
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Figure 4-2: Responsibility Assignment Matrix (RAM)
4.3 Schedule Management
The WBS provides a framework for detailed project planning and schedule development. As WBS
elements are established and work content is clearly defined in the WBS Dictionary, it is then possible
for the project team to determine the tasks (activities) and events (milestones) that are required to
successfully complete the project objectives and products. Tasks and events are identified for the effort
contained in each lowest-level WBS element. These are then included in project schedules and
organized in a format that enables management to determine the proper time-phasing of work. This
process should be done using an automated project management scheduling tool that has functional
capabilities for task sequencing, slack (float) calculations, task start/finish date generation, critical path
determination, constraint identification, and resource loading. As tasks for each of the lowest WBS
elements are input into the scheduling tool, various types of associated data are also input for each task,
such as description, duration, sequencing, responsibility, constraints, resources, and WBS coding. With
all task information in place in the schedule tool for all lowest-level WBS elements, the result is an
Integrated Master Schedule (IMS). Because WBS coding is included in the IMS, task networks (logic
networks) and other schedule data can be produced at the lowest detail or summarized to various levels
of the WBS structure for project management insight, assessment, and control. The NASA Schedule
Management Handbook can be referenced for additional scheduling process guidance.
NASA Work Breakdown Structure (WBS) Handbook Page 46
Project schedules are typically available at detailed, intermediate, and summary levels. The level of
schedule detail needed is dictated by the scope and complexity of the project work and the needs of
management for schedule visibility and control. Schedule levels and management levels need not
coincide with WBS levels. Generally there is no requirement for separate schedules for each WBS
level. However, if the appropriate WBS element numbers are assigned to each lowest-level task and
milestone contained in the IMS, then through data filtering all schedule items can be extracted and
formatted by lowest detail or summarized by any WBS level. The lowest level of each WBS element
should have at least one task or activity.
Since a product-oriented WBS serves as the framework for schedule development, then resulting
project schedules are also product-oriented. This type of schedule allows managers to monitor the
schedule baseline for the project's products to ensure that the project objectives are completed on time.
Prime contractors must also submit required schedule reporting, with CWBS coding included, to permit
government insight and control at the necessary levels of detail.
Project schedule management effort should be established as a sub-element of the standard level two
“Project Management” WBS element.
4.4 Cost Management
The WBS is a key tool used for assisting project teams in managing cost. By breaking the total product
into successively smaller entities, management can more readily verify that all work identified by the
WBS and budgeted for (and later charged against) actually contributes to the project objectives. By
using an approved project WBS to plan the total scope of work, it serves as the framework for cost
estimating, budgeting, accounting, and control of project costs.
The WBS structure and content definition provides a systematic approach to cost estimating that helps
ensure that relevant costs are not omitted. A project estimate that is based on the WBS helps NASA
management to ensure that budget development is credible and complete. When WBS elements and the
supporting work are scheduled, a solid basis for time-phased budgets is ready-made. The WBS also
provides a common framework for tracking the evolution of estimates (e.g., conceptual estimates,
preliminary design estimates, and detailed design estimates). The WBS can also provide a framework
for life cycle cost analysis.
As periodic project cost estimates are developed, each succeeding estimate is made in an attempt to
forecast more accurately the project's total cost. Basically, the estimates may be organized in two ways,
by WBS element or by code of accounts. Both support NASA's on-going efforts in preparing budgets
and evaluating contractor performance.
It is important to remember that NASA requirements for project management mandate that projects
implement a technical WBS which will be identical to the accounting WBS contained in the Agency
Core Financial System. Accounting transactions must be coded in such a way that they can be
identified to the specific project WBS element which incurred the transaction cost, and to the time
period when the transaction occurred. Since the WBS element number also serves as the financial
charge code, the accounting system can be programmed to accept charges at levels of the WBS
hierarchy where insight is necessary based on project management’s authorization.
NASA projects must follow NPR 7120.5, 7120.7, and 7120.8 requirements to use standard level two
WBS templates. Because of this, the standard level two elements can be used as categories to
NASA Work Breakdown Structure (WBS) Handbook Page 47
accumulate pertinent historical cost data. Such historical data can be used in conjunction with learning
curves, regression and other techniques to estimate the cost requirements for similar elements of new
projects. Subsequent cost data collected by NASA can be compared to the original estimates to
establish their validity, identify trends, and re-estimate future project needs. Contractor and other
performing entity data can also be included in this type of historical database if consistent WBS coding
is maintained.
Cost management effort should be established as a sub-element of the standard level two “Project
Management” WBS element.
4.5 Performance Management
Integrated performance management, also known as EVM begins with a product-oriented WBS that
accurately reflects all project work to be accomplished. As stated above, the WBS provides a
framework for organizing all technical, schedule, and budget planning. It should be noted that NASA’s
requirement for the technical and financial WBS to be one and the same will enhance a project team’s
ability to successfully correlate cost, schedule, and technical planning into a cohesive management
baseline. Proper use of the WBS as a common reference for integration of cost, schedule, and technical
management accomplishes the performance management objectives of defining and controlling project
work.
The integrated performance management process dictates using the same WBS in defining the work
scope, in scheduling (time-phasing) the work, and also in establishing budgets that correlate
appropriately. The illustration shown below in Figure 4-3 depicts in a simple overview how the
Performance Measurement Baseline (PMB) is derived. This figure shows how the time-phased
accumulation of resources that have been applied to the schedule provide a performance profile that is
used for measuring project performance. This baseline is used not only for measuring performance
accomplishment but also for deriving trend data for future project cost and schedule projections.
NASA Work Breakdown Structure (WBS) Handbook Page 48
Figure 4-3: WBS and the Development of the Performance Measurement Baseline (PMB)
In addition, the WBS is used to accumulate performance data and associated variances. This allows
NASA Project Control Account Managers (P-CAMs) and contractors to evaluate progress in terms of
performance for their specific project responsibilities. There is no need for separate performance
assessments to be made at levels above the CA because the WBS facilitates the summarization of data
for successively higher levels of management insight and oversight. By using the WBS, variances can
then be traced to their source areas.
Performance management effort should be established as a sub-element of the standard level two
“Project Management” WBS element.
4.6 Risk Management
Risks represent potential impacts to successful achievement of project goals and objectives. Project
risks typically fall into various defined categories such as technical, programmatic (cost, schedule,
resources), etc. A risk can also exist in any element of work content and at any time during the project
life cycle. Since a WBS serves as the common reference for all project cost, schedule, and technical
data, it only makes sense that it should also play an important role in managing risks (see Figure 4-4).
All risks identified during project implementation can typically be correlated to effort associated with
one or more WBS elements. As risks are logged into the risk management system, the WBS element
number will be a key data point for further tracking and mitigation planning. Risk mitigation or the
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lack of risk mitigation will many times impact cost and/or schedules for affected WBS elements.
Control of risk impacts is a critical management emphasis and as such will involve on-going mapping
to the WBS.
NEGLIGIBLE MINOR MAJOR SERIOUS CRITICAL
91 - 100%
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NEGLIGIBLE MINOR MAJOR SERIOUS CRITICAL
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NEGLIGIBLE MINOR MAJOR SERIOUS CRITICAL
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CONSEQUENCE
PROBABILITY
NEGLIGIBLE MINOR MAJOR SERIOUS CRITICAL
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CONSEQUENCE
PROBABILITY
NEGLIGIBLE MINOR MAJOR SERIOUS CRITICAL
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The WBS Provides a Common Reference Point for Documenting,
Managing, Tracking, and Communicating Program/Project Risks
Figure 4-4: WBS Serves as a Common Reference Point in Risk Management
Risk management effort within a project should be established as a sub-element of the standard level
two “Systems Engineering” WBS element.
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APPENDIX A: Acronym Listing
ATP Authority to Proceed
CA Control Account
CAM Control Account Manager
CM Configuration Management
COCD Commitment, Obligation, Cost and Disbursement
CWBS Contract Work Breakdown Structure
DRD Data Requirements Document
EIA Electronic Industries Alliance
EPO Education and Public Outreach
EVM Earned Value Management
GSE Ground Support Equipment
HQ NASA Headquarters
ICD Interface Control Document
ILS Integrated Logistic Support
IMS Integrated Master Schedule
MdM Metadata Manager System
MIL Military
NASA National Aeronautics and Space Administration
NFS NASA FAR Supplement
NPD NASA Policy Directive
NPR NASA Procedural Requirements
NSM NASA Structure Management
OBS Organizational Breakdown Structure
PCA Program Commitment Agreement
P-CAM Project Control Account Manager
PMB Performance Measurement Baseline
PMI Project Management Institute
PP Planning Package
RAM Responsibility Assignment Matrix
R&T Research and Technology
RFP Request for Proposal
RTOPs Research and Technology Objectives and Plans Summaries
S&MA Safety and Management Assurance
SE&I Systems Engineering and Integration
SOW Statement of Work
NASA Work Breakdown Structure (WBS) Handbook Page 51
STI Science and Technical Information
TCS Thermal Control System
TD Technology Development
V&V Verification and Validation
WBS Work Breakdown Structure
WP Work Package
NASA Work Breakdown Structure (WBS) Handbook Page 52
APPENDIX B: Glossary of Terms
Contract Work Breakdown Structure (CWBS) - A work breakdown structure of the products or services
to be furnished under contract. It is comprised of selected Project WBS elements specified in the
contractual document and the contractor's lower level extensions of those elements.
Control Account (CA) – An identified intersection of the Work Breakdown Structure (WBS) and
Organizational Breakdown Structure (OBS) at which responsibility for work is assigned to one
organizational unit and actual direct labor, material, and other direct costs (ODC) are compared with
the planned budget and the earned value for management control.
End Item - A final combination of end products components, parts, or materials which is ready for its
intended use; an item of software or documentation that is deliverable to a user or customer.
Integrated Master Schedule (IMS) - An integrated schedule developed by logically networking all
detailed program/project activities. The highest level schedule is the Master Schedule supported by
Intermediate Level Schedules and by lowest level detail schedules. See IMPR Format 6.
Metadata Manager (MdM) System - A web-based application that controls the creation, maintenance,
and archiving of the NASA Structure Management (NSM) structure and the NSM Coding System
codes.
Performance Measurement Baseline (PMB) - for accomplishing all authorized work scope in a project's
life cycle, which includes both NASA internal costs and supplier costs. The PMB is used to measure
project performance using earned value mangement, if required, or other performance measurement
techniques if EVM is not required. It is formed by the budgets assigned to scheduled control account
and the applicable indirect budgets. For future effort, not planned to the control account level, the
performance measurement baseline also includes budgets assigned to higher level WBS elements and
undistributed budgets. The PMB does not include UFE, or management reserve (MR) for contractors.
It equals the total allocated budget less management reserve.
Planning Package (PP) - A planning package is a logical aggregation of work within a CA containing
far-term effort which can be identified and budgeted in early baseline planning at a higher level, but
cannot yet be adequately defined into a WP.
Program - A strategic investment by a Mission Directorate (or Mission Support Office) that has defined
goals, objectives, architecture, funding level, and a management structure that supports one or more
projects.
Project - A specific investment identified in a Program Plan having defined goals, objectives,
requirements, life-cycle cost, a beginning, and an end.
Project Plan - A detailed plan which, when formally approved, sets forth the agreement between a
program manager and project managers, and defines the guidelines and constraints under which the
project will be executed.
Request for Proposal (RFP) - A solicitation used in negotiated acquisition to communicate government
NASA Work Breakdown Structure (WBS) Handbook Page 53
requirements to prospective contractors and solicit proposals.
Statement of Work (SOW) – A document containing a narrative description of the total work scope for
a project or contract.
Specification Tree - A graphic portrayal arranged to illustrate interrelationships of hardware and/or
software performance/design requirements specifications; normally, this portrayal is in the form of a
"family tree" subdivision of the specifications with each lower-level specification applicable to a
hardware/software item which is part of a higher-level item.
Subsystem - A functional entity within a system. The name given for the next level of breakdown
under a system.
System - One of the principal functioning entities comprising the project hardware within a project or
flight mission. Ordinarily, a system is the first major subdivision of project work.
Work Breakdown Structure (WBS) – A product-oriented hierarchical division of the hardware,
software, services, and data required to produce the program's or project's end product(s), structured
according to the way the work will be performed and reflecting the way in which program/project costs
and schedule, technical, and risk data are to be accumulated, summarized, and reported. The WBS
should be accompanied by a text document referred to as a WBS Dictionary that describes the work
content each element of the WBS in detail.
WBS Dictionary -A document that describes the work content of each WBS element, in product-
oriented terms, and relates each element to the respective, progressively higher levels of the structure,
as well as to the Statement of Work.
WBS Element - Any block or unique entry in a work breakdown structure regardless of level.
WBS Levels - The arrangement or configuration of a WBS which establishes the hierarchy of projects
to programs, systems to projects, subsystems to systems, etc.
Work Package (WP) – Natural subdivision of control accounts. A WP is simply a task/activity or
grouping of work. A WP is the point at which work is planned, progress is measured, and earned value
is computed.
APPENDIX C: Standard Project WBS Level 2 Templates and WBS Dictionary
Content Descriptions
A. SPACE FLIGHT PROJECT WBS Standard Level 2 Elements (see NPR 7120.5, Appendix H):
Standard Level 2 WBS elements for space flight projects are shown in the figure below. The standard
WBS template assumes a typical spacecraft flight development project with relatively minor ground or
mission operations elements. For major launch or mission operations ground-development activities
which are viewed as projects unto themselves, the WBS may be modified. For example, the spacecraft
element may be changed to reflect the ground project major deliverable (such as a facility). The
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elements such as payload, launch vehicle/services, ground system(s), and mission operations (system)
that are not applicable may be deleted. (Appendix E shows an example of a hardware contract work
breakdown structure that a hardware-development prime contractor might use.)
The following is the Space Flight Project Standard WBS Dictionary:
Element 01 - Project Management: The business and administrative planning, organizing, directing,
coordinating, analyzing, controlling, and approval processes used to accomplish overall project
objectives, which are not associated with specific hardware or software elements. This element includes
project reviews and documentation, non-project owned facilities, and project reserves. It excludes costs
associated with technical planning and management and delivery of engineering, hardware and
software.
Element 02 - Systems Engineering: The technical and management efforts of directing and
controlling an integrated engineering effort for the project. This element includes the efforts to define
the project space flight vehicle(s) and ground system, conducting trade studies, the integrated planning
and control of the technical program efforts of design engineering, software engineering, specialty
engineering, system architecture development and integrated test planning, system requirements
writing, configuration control, technical oversight, control and monitoring of the technical program, and
risk management activities. Documentation products include requirements documents, Interface
Control Documents (ICD), Risk Management Plan, and master Verification and Validation (V&V)
plan. Excludes any design engineering costs.
Element 03 - Safety and Mission Assurance: The technical and management efforts of directing and
controlling the safety and mission assurance elements of the project. This element includes design,
development, review, and verification of practices and procedures and mission success criteria intended
to assure that the delivered spacecraft, ground systems, mission operations, and payload(s) meet
performance requirements and function for their intended lifetimes. This element excludes mission and
product assurance efforts directed at partners and subcontractors other than a review/oversight function.
Element 04 - Science / Technology: This element includes the managing, directing, and controlling of
the science investigation aspects, as well as leading, managing, and performing the technology
demonstration elements of the Project. The costs incurred to cover the Principal Investigator, Project
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Scientist, science team members, and equivalent personnel for technology demonstrations are included.
Specific responsibilities include defining the science or demonstration requirements; ensuring the
integration of these requirements with the payloads, spacecraft, ground systems, and mission
operations; providing the algorithms for data processing and analyses; and performing data analysis and
archiving. This element excludes hardware and software for onboard science investigative
instruments/payloads.
Element 05 - Payload: This element includes the special-purpose equipment and normal equipment,
e.g., Ground Support Equipment (GSE), integral to the spacecraft. This includes managing, and
implementing the hardware and software payloads that perform the scientific experimental and data-
gathering functions on board the spacecraft, as well as the technology demonstration for the mission.
Element 06 - Spacecraft(s): The spacecraft that serves as the platform for carrying payload(s),
instrument(s), humans, and other mission-oriented equipment in space to the mission destination(s) to
achieve the mission objectives. The spacecraft may be a single spacecraft or multiple
spacecraft/modules (e.g., cruise stage, orbiter, lander, or rover modules). Each spacecraft/module of the
system includes the following subsystems, as appropriate: Crew, Power, Command & Data Handling,
Telecommunications, Mechanical, Thermal, Propulsion, Guidance Navigation and Control, Wiring
Harness, and Flight Software. This element also includes all design, development, production,
assembly, test efforts, and associated GSE to deliver the completed system for integration with the
launch vehicle and payload. This element does not include integration and test with payloads and other
project systems.
Element 07 - Mission Operations System: The management of the development and implementation
of personnel, procedures, documentation, and training required to conduct mission operations. This
element includes tracking, commanding, receiving/processing telemetry, analyses of system status,
trajectory analysis, orbit determination, maneuver analysis, target body orbit/ephemeris updates, and
disposal of remaining end-of-mission resources. The same WBS structure is used for Phase E Mission
Operation Systems but with inactive elements defined as "not applicable." However, different accounts
must be used for Phase E due to NASA cost reporting requirements. This element does not include
integration and test with the other project systems.
Element 08 - Launch Vehicle / Services: The management and implementation of activities required
to place the spacecraft directly into its operational environment, or on a trajectory towards its intended
target. This element includes launch vehicle, launch vehicle integration, launch operations, any other
associated launch services, and associated ground support equipment. This element does not include the
integration and test with the other project systems.
Element 09 - Ground System(s): The complex of equipment, hardware, software, networks, and
mission-unique facilities required to conduct mission operations of the spacecraft systems and
payloads. This complex includes the computers, communications, operating systems, and networking
equipment needed to interconnect and host the Mission Operations software. This element includes the
design, development, implementation, integration, test, and the associated support equipment of the
ground system, including the hardware and software needed for processing, archiving, and distributing
telemetry and radiometric data and for commanding the spacecraft. Also includes the use and
maintenance of the project test beds and project-owned facilities. This element does not include
integration and test with the other project systems and conducting mission operations.
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Element 10 - Systems Integration and Testing: This element includes the hardware, software,
procedures, and project-owned facilities required to perform the integration and testing of the project's
systems, payloads, spacecraft, launch vehicle/services, and mission operations.
Element 11 - Education and Public Outreach: Provide for the Education and Public Outreach (EPO)
responsibilities of NASA's missions, projects, and programs in alignment with the Strategic Plan for
Education. This element includes management and coordinated activities, formal education, informal
education, public outreach, media support, and website development.
B. INFORMATION TECHNOLOGY AND INSTITUTIONAL INFRASTRUCTURE PROJECT
WBS Standard Level 2 Elements (see NPR 7120.7):
The IT Standard WBS provides the needed flexibility for the wide variety of IT projects including
Software Development, Hardware Acquisition/Deployment, Service/Process Change, etc.
To align with the agency existing project standards, the Standard WBS for IT projects will follow the
structure listed below:
The following is the Information Technology Standard WBS Dictionary :
Element XXXXXX.01 - Project Management: All activities associated with business and administrative
planning, organizing, directing, coordinating, analyzing, controlling, status reporting, and approval
processes used to accomplish overall project objectives, which are not associated with specific
hardware or software elements. This element includes project KDP reviews and system engineering
reviews. It also includes all activities associated with awarding and managing project-related contracts,
including technical support contracts. Activities associated with planning and finalizing staffing
requirements, facilities, administrative and standard operating procedures are also included. It excludes
costs associated with technical planning and management and costs associated with delivering specific
engineering, hardware and software products.
Element XXXXXX.02 - Systems Engineering: The technical and management efforts of directing and
controlling an integrated engineering effort for the project. This element includes the efforts to define
the project IT system(s) and operations delivery processes, conducting trade studies, the integrated
planning and control of the technical program efforts of design engineering, software engineering,
specialty engineering, system architecture development and integrated test planning, system
NASA Work Breakdown Structure (WBS) Handbook Page 57
DRAFT
requirements writing, configuration control, technical oversight, control and monitoring of the technical
program. Documentation products include requirements and preliminary design specifications, interface
control documents (ICDs), and the system engineering review presentations.
Element XXXXXX.03 – Safety and Mission Assurance: The technical and management efforts of
directing and controlling the safety and mission assurance elements of the project. This element
includes design, development, review, and verification of practices and procedures and mission success
criteria intended to assure that the delivered product meets performance requirements and function for
its intended lifetime. This element excludes product assurance efforts directed at partners and
subcontractors other than a review/oversight function, and the direct costs of environmental testing.
Full compliance with applicable sections of NPD 8700.1 is required for each project
Element XXXXXX.04 – System/Modules Development All activities associated with designing,
developing and/or procuring hardware and software configuration items, developing prototypes at the
development facility and the resulting integration, unit testing, assembly and checkout. The detailed
design is completed for each subsystem and a composite detailed design specifies the relationship of
each subsystem or module.
Element XXXXXX.05 - System Integration, Verification and Validation: All activities associated with
testing, analyzing and evaluating in order to verify and validate that products meet specifications,
satisfy requirements and are operationally suitable and effective. This element includes system
integration and user acceptance testing.
Element XXXXXX.06 – Security Validation: The technical and management efforts of directing and
controlling the security related elements of the project. This element includes security assessment,
security categorization, Certification and Accreditation activities, scanning activities and final
validation for the capability to move into full operation.
Element XXXXXX.07– System Deployment: All activities required to deploy the
system/subsystems/hardware, etc. into the production environment using the ITIL ―Service Transition‖
process for ―Release and Deployment Management . The WBS includes all site preparation activities,‖
e.g., new power, installation of equipment racks, and cabling. Activities to ensure documentation of
standard operating procedures, planning for final security scans and any other activities required to
transition operations to a ―production facility are also included in this WBS. Deployment activities‖
for this WBS address both hardware and software or service/process deployment at either a single
production facility or at multiple sites. This WBS would be used for activities to complete the approach
for multi-site deployment.
Element XXXXX.08 – Operational Site Implementations: All activities required to implement (move
into daily operation) at a specific site. The WBS would be used to track site resource requirements and
scheduled site-specific activities for each site. Any site specific activities and resources would be
tracked in this WBS. Examples of site specific activities would be the site readiness review, a data
migration plan and a transition plan if migrating from one process/system to another.
Element XXXXXX.09 – Outreach and Training: All activities required to provide for the Education
and Public Outreach (EPO) responsibilities of NASA's IT projects in alignment with the Strategic Plan
for Education. This WBS includes management and coordinated activities, formal education, informal
education, public outreach, media support, and website development (if used for outreach activities).
Includes all activities associated with designing, developing, and delivering training services, aids
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C1. TECHNOLOGY DEVELOPMENT (TD) PROJECT WBS Standard Level 2 Elements (from
NPR 7120.8, Appendix K) - formerly Advanced Technology Development Project:
Standard Level 2 WBS elements for TD projects are shown below. The standard WBS template
assumes a typical TD project with no flight elements. For TD projects, additional WBS elements may
be added horizontally (i.e., at Level 2) as long as their content does not fit into the content of any
existing standard WBS elements. The elements that are not applicable do not need to be used (entered
into MdM). For TD projects managed as Space Flight Projects in accordance with NPR 7120.5, NASA
Space Flight Program and Project Management Requirements, the Space Flight Project WBS will be
used.
The following is the Technology Development (TD) Project Standard WBS Dictionary (from NPR
7120.8, Appendix K):
Element 01 -- TD Project Management: The business and administrative planning, organizing,
directing, coordinating, controlling, and approval processes used to accomplish overall project
objectives, which are not associated with specific hardware or software elements. This element includes
project reviews and documentation, non-project owned facilities, and project reserves. It excludes costs
associated with technical planning and management and costs associated with delivering specific
engineering, hardware, and software products.
Element 02 -- TD Project Analysis: System and Portfolio Analysis includes the process of developing
qualitative and quantitative understanding of key technical issues and drivers, including current
limitations and challenges. These analyses are the foundations that support development and
assessment of: goals, requirements, scope, risk/feasibilities, costs, design, integration, and operations.
Based on the systems analysis, the process further identifies and tracks the investment trade spaces and
NASA Work Breakdown Structure (WBS) Handbook Page 59
supports the project's ability to optimize its resources to maximize the return on investment within
acceptable risk exposure, budget, schedule, and performance requirements.
Element 03 -- Advanced Concepts: This WBS element encompasses low-level studies (possibly
including laboratory experiments) intended to explore the feasibility of new ideas or approaches to
accomplish programmatic or technical objectives. Often they are inspired by new scientific or technical
breakthroughs that open up new avenues for technological investigation. Advanced concept activities
can be an integral part of a specific technology project, or they can be separate technology activities
focused on broad topics. Typically, advanced concept activities are tied to long-term objects, though
this is not required, and due to their speculative nature, are generally considered high-risk. Also, they
tend to be managed in a looser manner than technology development. Advanced concept studies are a
principal means for identifying promising new opportunities for high payoff technology development.
Element 04 -- Technology Development: This WBS element encompasses the execution phase of
implementing a TD project plan. Typically, most of the lower level (Level 3 and below) WBS elements
associated with achieving the technical objectives (e.g., performance metrics) of the project are
contained within this element. TD projects span the gap from advanced concepts to engineering or
advanced development (Technology Readiness Level (TRL) 2/3 to TRL 6/7) and can begin and end
anywhere within this range. Once a project has started, technology development will include the
continual assessment of progress, redistribution of resources and schedule updates necessary to meet
key milestones within budget and schedule. When the intended outcome cannot be met within plan, re-
planning at the project level falls within Project Management. The primary deliverables, including
technical progress reports and documenting technical accomplishments, are part of this WBS element.
Element 05 -- Validation and Test: This element provides for specific activities to test and validate
products of technology development when those activities represent a critical aspect of the overall
technology development plan. Typically, a separate test and validation element will be part of the
project that intends to achieve TRL 6/7. The element encompasses the development hardware/software
test validation articles; development or acquisition of special test or validation equipment; scheduling
and staffing facilities or ranges; as well as the development and execution of the test or validation plan.
Often the full context of test and validation may not be known at the beginning of the project and will
be developed as required. In some cases, if extensive use of large-scale facilities is required or the
test/validation takes on the characteristics of a space flight project, it will be conducted as a flight
project (e.g., space-flight project) within this WBS element or transferred to a space flight project in
accordance with NPR 7120.5, NASA Space Flight Program and Project Management Requirements.
Element 06 -- Safety and Mission Assurance: Provides for directing and controlling the safety and
mission assurance elements of the project. This element includes design, development, review, and
verification of practices and procedures and success criteria intended to assure that the delivered
product meets performance requirements and function for their intended lifetimes. This element
excludes mission and product assurance efforts at partners/subcontractors other than a review/oversight
function.
Element 07 -- Education and Public Outreach: Provide for Education and Public Outreach
responsibilities of NASA's missions, projects, and programs in alignment with the Strategic Plan for
Education, including formal and informal education, public outreach, media support, and Website
development.
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Element 08 -- Technology Transfer: This WBS focuses principally on three types of activities: (1)
Transferring knowledge and technology development products developed within the project to non-
NASA entities that are not part of the project either as direct participants or as direct beneficiaries of the
project, (2) Acting on behalf of the project to identify and transfer into the project knowledge or
technology from sources not directly participating in the project or benefiting from the project, and (3)
Providing supporting expertise to transfer knowledge and technology products between NASA and
non-NASA entities, including project participants. Typically, technology transfer requires special
expertise not associated with any specific project or required to accomplish primary technical
objectives/ milestones/metrics. Also, technology transfer activities are often an integral part of the
overall project plan but not necessarily an integral part of the technology development process. As
such, it is often appropriate to fund, implement, and manage technology transfer as a distinct element of
a TD project.
C2. RESEARCH & TECHNOLOGY (R&T) PORTFOLIO PROJECTS WBS Standard Level 2
Elements (from NPR 7120.8, Appendix K): - formerly Basic and Applied Research Portfolio WBS
Standard Level 2 WBS elements for R&T Portfolio Projects are shown below. The template is used to
specify the integrated budget within the R&T Portfolio Project Plan. For R&T Portfolio Projects,
additional WBS elements may be added horizontally (i.e., at Level 2) as long as their content does not
fit into any existing WBS elements. The elements that are not applicable need not be used. For R&T
Portfolio Projects managed as Space Flight Projects in accordance with NPR 7120.5, the Space Flight
Systems Project WBS will be used.
Following is the R&T Portfolio Project Standard WBS Dictionary (from NPR 7120.8, Appendix K,
formerly Basic and Applied Research Portfolio Standard WBS Dictionary):
Element 01 -- R&T Portfolio Project Management: The management activity is paid for with R&T
Portfolio Project dollars. This includes salaries and travel (e.g., civil service personnel,
Intergovernmental Personnel Act assignees, detailees), peer review management (contractor support,
travel, and honoraria), and meetings and conferences.
Element 02 -- Funded Research/Awards: The awards from either competed or directed elements of
the R&T Portfolio Project. This includes but is not limited to grants, Independent Assessment Teams,
Research and Technology Objectives and Plans Summaries (RTOPs), and contracts. This element may
also include awards for Education and Public Outreach.
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Element 03 -- Facilities, Test beds, and Operations: The non-award infrastructure costs that support
the R&T Portfolio Projects.
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APPENDIX D: Standard Data Requirements Document (DRD)
DATA REQUIREMENTS DESCRIPTION (DRD)
1. DPD NO.: XXX ISSUE: Standard 2. DRD NO.: STD/MA-WBS
3. DATA TYPE: 2 4. DATE REVISED:
5. PAGE: 1/2
6. TITLE: Work Breakdown Structure (WBS) and WBS Dictionary
7. DESCRIPTION/USE: To establish a product-oriented framework for reporting program cost, schedule, and
technical performance. To provide a basis for uniform planning, reporting status, program visibility, and
assignment of responsibilities.
8. OPR: CS10 9. DM:
10. DISTRIBUTION: Per Contracting Officer's letter
11. INITIAL SUBMISSION: Draft with proposal
12. SUBMISSION FREQUENCY: 30 days after Authority to Proceed (ATP), update as required. Revised pages
shall be submitted 10 calendar days after contract WBS changes (following Government approval).
13. REMARKS: Reference is made to NPD 7120.4 (Current Revision), NASA Engineering and Program/Project
Management Policy, and NPR 7120.5 (Current Revision), NASA Space Flight Program and Project
Management Requirements, NPR 7120.7 (Current Revision), NASA Information Technology and Project
Management Requirements, NPR 7120.8 (Current Revision), NASA
Research and Technology Program and
Project Management Requirements and NASA
Work Breakdown Structure (WBS) Handbook (Current
Revision). These documents shall be used as guides in the preparation of
the WBS and the WBS dictionary.
14.
INTERRELATIONSHIP: DRD STD/MA-IMS, Integrated Master Schedule.
15. DATA PREPARATION INFORMATION:
15.1
SCOPE: The WBS establishes a product-oriented logical subdivision of
hardware, software, services, facilities,
etc., that make up the total project scope of work. The WBS Dictionary
provides a narrative description of the
tasks and effort to be performed in each WBS element.
15.2 APPLICABLE DOCUMENTS: None
15.3
CONTENTS:
The WBS and WBS Dictionary are two distinct project documents used for defining
the
approved project scope of work. The contents of each document are detailed in the following paragraphs:
a. WBS - A logical, hierarchical display of the subdivision of all project work to be completed. The WBS
shall include the approved element title and element number.
b. WBS Dictionary - The WBS dictionary shall describe and document the work content of every WBS
element and relevant efforts associated with each element (e.g., design, development, and manufacturing).
The
WBS dictionary shall be arranged in the same order as the contract WBS. The WBS dictionary
shall
include the following for each WBS element:
1. WBS element title.
2. WBS element code.
3. WBS element content description (including quantities, relevant associated work, and contract end
items where applicable).
4. WBS Index.
5. Statement of Work paragraph number.
6. Specification (number and title) associated with the WBS element (if applicable).
7. Contract line item associated with the WBS element.
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8. Date, revision number, revision authorization and approved changes.
NASA Work Breakdown Structure (WBS) Handbook Page 64
DRD Continuation Sheet
TITLE: Work Breakdown Structure (WBS) and WBS Dictionary DRD NO.: STD/MA-WBS
DATA TYPE: 2 PAGE: 2/2
15. DATA PREPARATION INFORMATION (CONTINUED):
9. Contract Identification Number.
10. Budget and reporting number (i.e., Charge Code).
15.4
FORMAT : The WBS shall be in a chart format showing element relationships, arranged in the same order as
the WBS provided in the Request for Proposal (RFP). The WBS Dictionary shall be ordered in consonance
with the
WBS index and shall reference each WBS element by its identifier and name.
15.5
MAINTENANCE : Changes shall be incorporated by complete reissue.
*Instructions:
Applicability Instructions: This deliverable is a requirement for all projects and may be tailored on an as-needed basis to
meet unusual and/or specific project needs. Tailoring of this DRD shall be coordinated with the responsible OPR.
Preparation Information: Draft contract WBS and Dictionary shall be prepared in response to the Government RFP for
Government approval/disapproval. The contractor shall expand the WBS down to the level at which the work will be
accomplished. Formal contract WBS shall be in accordance with contractor/Government agreement reached during
negotiations.
Statement of Work Words: The contractor shall prepare and submit a Work Breakdown Structure (WBS) and WBS
Dictionary in accordance with DRD STD/MA-WBS.
NOTE: The instructions on this DRD are not a part of the DRD and should not be included in a DPD.
NASA Work Breakdown Structure (WBS) Handbook Page 65
APPENDIX E: Contractor CWBS Example
Following is an example of a hardware contract work breakdown structure. This example is from the
Ares Project and reflects the prime contractor CWBS for the First Stage hardware development.
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National Aeronautics and Space Administration
NASA Headquarters
Washington, D.C. 20546
NASA Work Breakdown Structure (WBS) Handbook Page 67
