This report focuses on the activities and findings of the fourth phase of research carried out at Carnegie-Mellon University (CMU) on the development of user documentation for computer-aided design (CAD) systems. The first of four major sections provides an overview of recent research, issues involved in the research, and implications of the findings that will enhance the design process as it is practiced by engineers and industrial designers. The second section reports on user process research, which involved the observation of approximately 50 designers, design students, engineers, and draftsmen. Topics addressed include the character of the design process, selective refinement of visual images created and used in the process of problem solving, and techniques used to manage the large amount of external information used by the designer in reaching a final solution. Several concepts that should influence future development of computer-aided design software manuals and computer manuals in general are identified in the third section, which discusses the development of the second module of the CMU CADAM Manual for IBM (International Business Machines). Computer-assisted instruction (CAI) for CADM design software is compared to printed documentation in the fourth section. The appendix includes background on the development of documentation for CADAM, CAI program documentation, and CAI testing materials. (MES)