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Project Management Orientation

What Is Decomposition?  

Decomposition is the subdividing of the major project deliverables into smaller, more manageable components.
  
The purpose of decomposition is to identify the top-level elements of the project and then divide the elements into manageable pieces for scheduling and tracking.  This process is used to develop the PBS and the WBS.

The OBS shows the project organizational unit responsible for each of the deliverables and components.

Types of Breakdown Structures 

There are three types of breakdown structures.  Move your  mouse pointer over the name of each breakdown structure to read a description of it.

These structures are techniques used to show relationships and dependencies among the project elements as part of the project shaping and definition.
OBS.  This structure displays resources.  The OBS depicts the relationship between the subprojects and organizational units of the project.  It describes the team structure of the organizational units and the reporting relationships between the delivery organization and performing organizations, including subcontractors.
PBS.  This structure is a hierarchy of project work products, including a special work product called the deliverable.  The PBS focuses on what must be produced and shows the items the project team makes, reuses, or buys.  It is a grouping of work product elements.
WBS.  This is a hierarchy of project work activities.  The WBS is a decomposition hierarchy of all the activities necessary to produce all of the project work products.  The hierarchy has as many levels as required to define all the work.  Top-level activities are broken down into second-level activities that, in turn, are broken down into third-level activities and so on.  The WBS focuses on how the work products and project solution will be built.
1: Getting Started
2: Define the Project Team
3: Team Management
4: Identify and Validate Requirements
5: Create Decomposition Structures
6: Risk Management
7: Project Estimates
8: Project Schedules
9: Change Management
10: Project Control and Execution
Defining the Project
11: Project Management Review
12: Project Closeout
13: Project Management Tool Suite
14: Self-Assessment and Final Exam
Fast Points
Concepts
Seven Keys
Case Study
WWPMM
Mentor
Check Point
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