2. The different types and levels of decisions

There are three types of decisions:

• certain decisions: they have zero risk because the outcome of the decision is already known;

• random decisions: some of the variables used to make the decision are not fully controlled;

• uncertain decisions: some of the variables involved in making a decision are not at all under control.

Similarly, there are three levels of decision-making:

• strategic decisions: at this level, decisions determine the purpose of the project; they are centralized at a high hierarchical level (management committee or steering committee); they commit the project over the long term and are often irreversible;

• tactical decisions: at this level,...