It is important that on every project, the project decision makers are clear about what is expected from them in terms of their level of authority to take decisions, who they report to, and what their responsibilities are. PRINCE2 defines a flexible project management team structure which is suitable to be used on any type of project.
Within this project management team PRINCE2 defines a set of roles and responsibilities which can be adapted to suit the needs of each project. In PRINCE2 the project management team are appointed even before the project begins and can be refined as needed throughout the project.
Clearly defined roles and responsibilities reduces risk
By clearly defining the roles and responsibilities of the project management team, it helps to avoid the problems which can occur when people are not clear what is expected from them. These types of projects are often beset by communication problems and are a common reason why projects fail.