Work breakdown structure (WBS) is yet another very important aspect and deliverable of the project planning process. In this stage, you break the project into small and atomic individual activities that can be managed efficiently. In a work breakdown structure, you need to identify the smallest units of the work items that can be started and completed as a unit. A work breakdown structure provides a bird’s eye view of the project and helps identifying various dependencies in the project. Work breakdown structure is the key deliverable of the project planning and forms an input for various planning activities.
For the project management team, a work breakdown structure is a key deliverable. It is a decomposition of a project into smaller components. Each component by itself has a well defined deliverable and might be an input for another component. Creating a work breakdown structure enables the team to organize the entire work of the project into manageable sections and avoid any ambiguity.
According to the Project Management Body of Knowledge (PMBOK) guide, the work breakdown structure is defined as “A hierarchical decomposition of the total scope of work to be carried out by the project team to accomplish the project objectives and create the required deliverables.” A component of element of a work breakdown structure can be data, product, service, or it can be a combination of these elements. A well defined work breakdown structure not only provides you with a framework that you can use to create a detailed cost estimation and control, but also enables you to create a detailed schedule and help controlling it.
When you create a work breakdown structure, it is essentially a hierarchical decomposition of complex project into simple phases, deliverables, and work packages. It is usually an inverted tree structure; with each branch of this tree you indicate a subdivision of efforts required to accomplish an objective. To create a work breakdown structure, you start with the final objective of the project and then subdivide it into manageable components. You can define these components based on the size, duration, and responsibility. Each component includes all steps that the team needs to perform for achieving the objective.
One of the most important objectives of creating the work breakdown structure is to provide a framework for dividing work into definable units of work. You can use this structure for overall planning and control of the project and even to define the statement of work. Further, you can use the work breakdown structure to establish schedule, cost, and labor hour reporting.
A work breakdown structure also enables you to sum subordinate costs of the tasks and materials of the components into the tasks and materials of the parent component. You must provide a description of the tasks to be performed for each element of the work breakdown structure. You can also use the work breakdown structure to define the complete scope of the project.
One thing you must keep in mind is to focus the work breakdown structure around product of the project and not around the tasks needed to perform to produce the product.