Projects have different ways to be identified and therefore they all have different amounts of information available at start up. PRINCE2 calls the trigger for the project the project mandate, which is provided by the authority which is commissioning the project.

The project mandate applies to whatever information is used to trigger the project, be it a feasibility study or the receipt of a 'request for proposal' in a supplier environment.

A mandate should contain the terms of reference for the project and contain sufficient information to identify at the least the Executive of the Project Board.

The project board must be provided with sufficient information to make the decision to initiate the project. The project brief is prepared for this purpose.

The effort involved in Starting Up a project will vary from project to project. For example, if a project is part of a programme, the programme itself should provide the project brief and will appoint some, if not all, members of the project board.

The preparation of the outline Business Case and the assembling of the Project Brief (which are parallel and iterative activities) require regular and frequent interaction and consultations between the Project Manager, the Project Board members and other stakeholders. The more time spent on getting the requirements clearly captured during the Starting up a Project process, the more time will be saved during project delivery by avoiding issues, exceptions and replanning.