The decision about conducting a Gateway Review is based on the complexity/risk assessment using a Project Profile Model (PPM). This assessment is done by departments.
The PPM is intended to provide a standard set of high-level criteria against which Senior Responsible Owners can assess the intrinsic characteristics and degree of complexity of a proposed procurement project, in order to establish the appropriate:
control structures (including Gateway Reviews);
risk profile and corresponding risk strategy; and
design approach (for example, delivering the project in several increments or modules to help reduce complexity).