Defining Scope and WBS
According to PMBOK defining scope is the process of defining a clear and detailed explanation of the Project/Product. Project Scope clarifies the work which is to be done in the project. It describes the boundaries of a project including what is included in the project and what is NOT included in the project or exclusions.
For most projects, the list of the requirements of the project exceeds the available time, resources and budget. This limitation means that not all the expectations of the stakeholder can be met. The list of the work which is to be done as well as the work which is NOT supposed to be done in the project should be created so that the project team spend the resources on the tasks which are in line with project objectives.
The Project Charter, Project Requirement, and the Organizational Process Asset are the inputs of the process of defining scope. The PM should develop scope statement document in which the deliverables of the project are described in detail. Expert judgment is recommended to be applied to investigate the information in technical details. Other units of organization, consultants, field experts, sponsors, and stakeholders might be the source of necessary knowledge. However, many deliverables are too big to be managed on their own. In order to monitor the progress of the deliverables, they should be cut into the small chunks of work and that is where the creation of Work Breakdown Structure (WBS) helps.
What is Work Breakdown Structure (WBS)
The WBS is deliver-oriented hierarchical decomposition of the work which is to be performed by the project team to achieve the project objectives and to create project’s deliverables. The lowest layer of the WBS is called ‘Work Package’ and can be assigned, resourced, scheduled, and budgeted. It is also a detailed description of the project tasks and can be monitored and controlled by PM. It is critically important as the progress of the work package is the indication of the progress of the project.
As PM might not know about all aspects of the deliverables in detail, he is not able to create the WBS based on his own knowledge. In large projects, the few top levels of the WBS are created by a team. The work package as a very specific and detailed description of the work can also be prepared with the aid of experts.