These guidelines for communicating effectively the details of computer model design and operation to persons with varying interests in a model recommend the development of four different types of manuals to meet the needs of managers, users, analysts and programmers. The guidelines for preparing a management summary manual suggest a broad spectrum of general information required for decision making. It is recommended that the user's manual include practical aspects of the model and its application to the user's specific programs. Technical details which are needed for maintenance and modification of the model are suggested for the programmer's manual, while processing aspects and the underlying analytical methods and algorithms are recommended for analysts. Each set of guidelines contains an introduction, a description of the model, content sections and subsections, and suggested appendices to the model. Emphasis is placed on explaining the capabilities and limitations of the model. A 21-item bibliography is included. (CHC)