work breakdown structure

A WORK BREAKDOWN STRUCTURE (WBS) IS A DECOMPOSITION OF ALL THE WORK NECESSARY TO COMPLETE A PROJECT. A WBS IS ARRANGED IN A HIERARCHY AND CONSTRUCTED TO ALLOW FOR CLEAR AND LOGICAL GROUPINGS, EITHER BY ACTIVITIES OR DELIVERABLES. THE WBS SHOULD REPRESENT THE WORK IDENTIFIED IN THE APPROVED PROJECT SCOPE STATEMENT AND SERVES AS AN EARLY FOUNDATION FOR EFFECTIVE SCHEDULE DEVELOPMENT AND COST ESTIMATING. PROJECT MANAGERS TYPICALLY WILL DEVELOP A WBS AS A PRECURSOR TO A DETAILED PROJECT SCHEDULE. THE WBS SHOULD BE ACCOMPANIED BY A WBS DICTIONARY, WHICH LISTS AND DEFINES WBS ELEMENTS.

The goals of developing a WBS and WBS Dictionary are 1) for the project team to proactively and logically plan out the project to completion, 2) to collect the information about work that needs to be done for a project, and 3) to organize activities into manageable components that will achieve project objectives. The WBS and WBS Dictionary are not the schedule, but rather the building blocks to it. The progression of WBS and WBS Dictionary development is as follows:

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The WBS and WBS Dictionary should not be static documents. WBS construction is subject to project management progressive elaboration, and as new information becomes known, the WBS should be revised to reflect that information. A Project Team that has substantial changes to its WBS should reference the project’s Change Management Plan for guidance on management of changes to project scope.

Example

Below is a simplified WBS example with a limited number of organizing levels. The following list describes key characteristics of the sample WBS: • Hierarchical Levels – contains three levels of work • Numbering Sequence – uses outline numbering as a unique identifier for all levels • Level one is 1.0, which illustrates the project level. • Level two is 1.X (1.1, 1.2, 1.3, etc.), which is