Decomposition
Decomposition is a technique used to divide and subdivide the project scope and deliverables into smaller, more manageable parts until the work is defined at the work package level.
Explanation
Decomposition is the primary technique used in the Create WBS process and is also used in the Define Activities process. In scope management, decomposition breaks the project scope statement and deliverables into progressively smaller, more manageable components, ultimately producing work packages at the lowest level of the WBS.
The process typically follows these steps: identify and analyze the deliverables, structure and organize the WBS (by phase, deliverable, or subproject), decompose upper WBS levels into lower-level components, develop and assign identification codes to WBS components, and verify that the degree of decomposition is adequate for management and control purposes.
A key principle governing decomposition is the 100% rule: the total scope of each parent element must be fully accounted for in its child elements, with nothing missing and nothing duplicated. Over-decomposition should be avoided, as it can lead to excessive management overhead without proportional benefit. Under-decomposition can leave work packages too large to estimate and control reliably.
Key Points
- •Primary technique in Create WBS and Define Activities
- •Breaks scope into progressively smaller, manageable components
- •Must follow the 100% rule at every level
- •Avoid both over-decomposition and under-decomposition
Exam Tip
Decomposition is used in two processes: Create WBS (to break deliverables into work packages) and Define Activities (to break work packages into activities). Know both applications.
Frequently Asked Questions
Related Topics
Create WBS
Create WBS is the process of subdividing project deliverables and project work into smaller, more manageable components.
Work Breakdown Structure (WBS)
A work breakdown structure (WBS) is a hierarchical decomposition of the total scope of work to be carried out by the project team to accomplish the project objectives and create the required deliverables.
Work Package
A work package is the lowest level of the work breakdown structure, representing a deliverable or project work component that can be estimated, scheduled, monitored, and controlled.
Planning Package
A planning package is a WBS component below the control account with known work content but without detailed schedule activities, used as a placeholder for future planning.
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Part of
Scope Management
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