The lack of adequate support for the development of mathematical process models confines the application of model-based techniques in the design and operation of complex chemical plants. One important issue in addressing this problem is the systematization of the process of model development (called modeling process in the following). In order to provide a basis for further investigations into the modeling process and to prepare the development of computer-aided modeling tools supporting the modeling process, this contribution deals with general properties of the modeling process and discusses to which degree of granularity the modeling process can be formalized. A modeling example will serve to suggest a first set of canonical modeling steps, which allow to classify and continuously extend procedural modeling knowledge.