The project mandate should provide the terms of reference for the project. These define the purpose and objectives of the project, setting the foundation for further project definition and planning in subsequent processes. References: PRINCE2 Foundation Training Manual; PRINCE2 2017 Foundation handbook.

The process that ensures key roles and responsibilities are allocated before a decision is made to initiate a project is 'Starting up a Project'. This process is crucial as it involves the appointment of the project management team and ensures that there is a clear understanding of the project's initial structure and approach before formally initiating the project.References: PRINCE2 7 Foundation handbook and documents.