The PID, in conjunction with supporting benefits management plan, communications plan and quality plan gives the definition, direction and scope of the project. It is the umbrella of the project that collects together all the critical information needed to manage the project and to aid the decision making of the board. It is a living document and should be updated at key decision points to reflect the current status of the project lifecycle.
The project manager is responsible for the preparation and production of the PID. A useful starting point in the production of the PID is to transfer relevant information from the business case. The project manager must actively engage with key stakeholders to gather the relevant input to support the PID.