The primary uses of the project plan are to document planning assumptions and decisions, facilitate communication among stakeholders, and document approved scope, cost, and schedule baselines.
The objective of a project plan is to define the approach to be used by the Project team to deliver the intended project management scope of the project.
At a minimum, a project plan answers basic questions about the project:
- Why? - What is the problem or value proposition addressed by the project? Why is it being sponsored?
- What? - What is the work that will be performed on the project? What are the major products/deliverables?
- Who? - Who will be involved and what will be their responsibilities within the project? How will they be organized?
- When? - What is the project timeline and when will particularly meaningful points, referred to as milestones, be complete?