Work Breakdown Structure (WBS) and Gantt Charts

Among the many details of a project are the required tasks and schedule. Every project, of course, needs a schedule, but the project team first needs to define the specific work tasks required to complete the project. A key tool for this process is the work breakdown structure, or WBS.

The WBS 

A WBS is a graphic decomposition of the individual tasks required for the project to be completed. Depending on the complexity of the project, the WBS may be fairly general or very detailed. Each box in a WBS chart will represent a work package, which is the lowest group of tasks that can be managed, analyzed, and controlled in terms of time and cost.

The readings below will provide more detail and include a simple example for finding a new home. This project might be separated into several sets of tasks—work packages—such as the following:

  • choose location
  • select a new home
  • sell current home
  • occupy new home

Some or all of those work packages might be further divisible, depending on the level of effort required for such tasks. For example, there are many subtasks required to selecting a new home, such as finding a real estate agent and determining the type of home to purchase. Subtasks usually have an order in which they must be completed. For instance, you would not be able to make an offer before you were determined prequalified for a loan.

Gantt Chart 

Once these work packages are defined, the project team can create a flowchart showing the interrelationships among the work packages. Entering those work packages into Microsoft Project will create your project Gantt chart. Microsoft Project will also allow you to create estimated schedules for your work packages and the project as a whole. From that chart, the team will be able to determine the project’s critical path—the longest path through your project schedule that will result in the latest project completion date. Your critical path must (1) appear in red, (2) start from the first day of your project, (3) stretch until the last day of the project, and (4) contain no breaks except for nonworking time, such as holidays.