During the 'Initiating a Project' process, the project manager develops key information, including the detailed Project Initiation Documentation (PID), which enables the project board to decide whether to proceed with the project. This information outlines the approach, plans, and controls that will govern the project, providing a foundation for detailed planning and informed decision-making by the project board.References:
PRINCE2 7 Foundation materials on the 'Initiating a Project' process.

Section: Volume B
Explanation/Reference: http://prince2.wiki/Business_Case