Given that the quality of models significantly affects the outcome of their application, it is important to reflect on the process by which they are actually constructed. This is addressed by the proposed Framework for the Constitution of Modelling Processes, which is presented here along with a few examples of its practical application. This framework is founded on Projective Constructivist Epistemology and provides a generic description of modelling processes, including their purpose, behaviour and structure. The framework may serve as a meta-model for the understanding, classification, use and development of the many different contributions to the field of modelling. Over the past five years, the framework has been actively researched, developed and applied in a variety of practical contexts, including the public, military and business sectors.