Benefits of the Work Breakdown Structure

Wikipedia defines the work breakdown structure, or WBS as it is known, as this:

A work breakdown structure (WBS) in project management and systems engineering, is a tool used to define and group a project’s discrete work elements in a way that helps organize and define the total work scope of the project.

The WBS provides the project manager and team with the necessary framework of tasks going forward to create detailed cost estimates and also to provide major input to project task scheduling at the most detailed and accurate level possible.  By going through the WBS motions, the project manager and team will have a pretty good idea whether or not they’ve captured all the necessary tasks, based on the project requirements, that are going to need to happen to get the job done.

Four key benefits to developing a WBS are:

#1 – WBS forces the team to create detailed steps

The WBS forces the project manager, team members, and customers to delineate the steps required to build and deliver the product or service. The exercise alone encourages a dialogue that will help clarify ambiguities, bring out assumptions, narrow the scope of the project, and raise critical issues early on.

#2 – WBS lays the groundwork for schedule and budget

It lays the groundwork for developing an effective schedule and good budget plans. A well-defined WBS enables resources to be allocated to specific tasks, helps in generating a meaningful schedule, and makes calculating a reliable budget easier.

#3 – WBS creates accountability

The level of detail in a WBS makes it easier to hold people accountable for completing their tasks.  With a defined WBS, people cannot hide under the “cover of broadness.” A well-defined task can be assigned to a specific individual, who is then responsible for its completion.

#4 – WBS creation breeds commitment

The process of developing and completing a WBS breeds excitement and commitment. Although the project manager will often develop the high-level WBS, he will seek the participation of his core team to flesh out the extreme detail of the WBS. This participation will spark involvement in the project.

The downsides (sort of)

Of course, developing a WBS is not easy. It can be a painstaking process.  And it can take quite a bit of time. A large WBS (one that identifies several thousand activities) can take many, many hours to develop. For another, it requires effort. There is a knowledge transfer and exercise of brainpower. The larger the scope of the project, the larger the WBS will be. More people must provide input and then approve the portion they are responsible to perform. Finally, the WBS requires continual refinement. The first iteration is rarely right and as the project changes, so does the WBS.

Even after considering the downsides, the overall advantages still outweigh the known challenges. A good WBS makes planning and executing a project easier and lays the groundwork for the schedule, the tracking, the budgeting, and all the accountability throughout the rest of the engagement.

4 Comments to “Benefits of the Work Breakdown Structure”

  • Until you have a solid understanding of the work to be done, you can’t schedule it, you can’t staff it, and you can’t cost it. The larger the project, the more deliverables, and the more steps required to produce them (unless you’re talking about The Great Wall of China, which was more about repeating a relatively small number of steps for several dozen generations). Consequently, the more complex WBS adds even more significant value, in that it provides opportunities to seek out economies of scale (TGWoC), or alternative approaches (buy, lease, outsource) for some deliverables to simplify management of the project.

    A good WBS just puts all the cards on the table.

  • Thank you Dave. Very true words – especially that last statement.

  • Brad,

    Good material. But a few corrections. MIL-STD-881C is being reviewed and ready for release in June. This should be the starting point for any WBS discussions.

    #1: The WBS does not contain a time scale or a sequence of the work. That is the Integrated Master Schedule. The WBS is the “product structure.” The WBS defines the logical relationship among all program elements to a specific level (typically Level 3 or 4) of indenture that does not constrain the contractor’s ability to define or manage the program and resources.

    #2: If you build the WBS with the terminal nodes as a deliverable or a service that produces a deliverable, then the Work Package (and Planning Package) paradigm can be used. This is a nice fit with Agile as well as traditional project life cycles.

    #3: Don’t use the WBS to create the accountability. Use the Responsibility Assignment Matrix. This connects the WBS with the OBS (Organizational Breakdown Structure).

    #4: Yes, the WBS serves as a coordinating medium. Through the WBS work progress is documented as resources are allocated and expended. Performance, cost, schedule, and technical data are routinely generated for reporting purposes. The WBS is the infrastructure to summarize data for successive levels of management and provide appropriate information on projected, actual, and current status of the individual elements.

    Regarding the downsides. there are none when seeking to increase the probability of success for the project. Tedious? Doesn’t have to be, Use a tool like MindJet ( to build the WBS in an interactive manner with the team fully engaged. This includes the customer. With this hierarchical graphical representation, the IMS can be generated automatically (export to MSFT project). Then the Work Packages (or Tasks) sequenced, and then durations laid in for a candidate IMS.

    Care needs to be taken though on changing the WBS, since the product and process structure and eventually the cost allocations and mapping to the OBS are part of the integrated view of the project. WBS’s do change, even on formal programs, but only with change controls.

    Here’s a PMI workshop on Establishing the Performance Measurement Baseline (PMB). This is the end result from your efforts described in the post. The WBS is part of the process to build the PMB.