Defining The Project Management Work Breakdown Structure

In Project Management, there is a concept known as the Work Breakdown Structure (often denoted by the acronym WBS.) The WBS is helpful for identifying the overall project scope, then breaking that down into planned outcomes, using a tree hierarchy structure.

An outcome is the desired end result of the project, so it can be estimated or predicted with a fair degree of accuracy. On the other hand, there is the planned action which should not be included into the WBS. A planned action of any kind should be integrated into the project plan instead. Planned actions are harder to estimate and predict, compared to planned outcomes.

When creating a WBS, it is necessary to understand and adhere to the 100% Rule which means that all the work that is delineated by the project scope will be part and parcel of the WBS. This is inclusive of any deliverables (defined as interim, external, and internal.) This means all work that is not part of the Project should be left out, because then the coverage of the WBS would total more than 100%.

A Product Breakdown Structure is to be used for any new product development projects, as part of the creation of a WBS based on planned outcomes. A Feature Breakdown Structure is applicable for creating WBS for feature-based software development projects. On the other hand, if a deliverable-oriented WBS is formed, this would apply to projects that deal with professional services and encompass integration of any planned deliverable into the WBS.

It is important the Project Manager creating the WBS should avoid any ambiguity in defining the elements, to prevent any unnecessary overlap.