Three long term mechanical engineering design projects spanning 24 months, 12 months, and 4 months are examined in this thesis. These projects are used to explore the development of a way to represent information flow throughout the design process with respect to design tools used. This is a first step in a broader effort to formalize (1) modeling of design processes, (2) establishing case study research as a formal approach to design research, and (3) developing new design process tools.;A survey of existing models compares the differences between current approaches and the limitations of each. Inspired by IDEF0, an altered process model is presented in an attempt to increase the information captured by the designer when using and constructing the process models. The name of the model is Design Enabler Information Maps (DEIM) and its requirements needed for construction are discussed in the context of the three case projects.;By developing a DEIM representation for each project, this thesis explores the benefit of this approach. In constructing a DEIM of a project, design activities with no productive merit, or design process dead-ends are identified. Information that is critical to design process completion is also identified in the context of its application. Furthermore, the need of a formal tool to represent complex design processes is established. The observations drawn from this thesis lay a foundation enabling future designers to better understand, represent, modify, and complete design processes by using case studies in design research.