The 100% Rule of the WBS

Posted on January 26, 2010 by


A Work Breakdown Structure (WBS) is a deliverable-oriented hierarchy of the work to be done on a project. So if your project is to write a paper on puffins, “Puffin Paper” would be the highest level of the hierarchy, and below it could be “Puffin Research,” “Paper Outline,” “Draft Paper,” and “Proofed Paper.”  These activities could then be broken down even further—for example proofing the paper could involve both checking spelling through the software used to write the paper and having a friend read the paper to check for mistakes. The 100% Rule states that your WBS must account for ALL of your project’s work. So, not just the typing of the paper, but the proofing, etc. as well. It can be easy to leave out the specific project management tasks of a project, such as developing a project management plan or identifying risks, but they should be included as well. The 100% Rule also means that every component in the WBS should be fully covered by the components below it. For example, a proofing component should include not only the ways of finding the errors but the action of correcting them.