WITH THE publication in recent years of such important works as Colby's1 computer simulation of a neurotic process, Bellman's2 analysis of psychiatric interviewing in terms of decision theory, Feigenbaum's3 studies of simulation of verbal learning behavior, Gullahorn's4 models of social behavior, and Newell and Simon's5 simulation of human thought, the potentiality of computer simulation as a tool of psychiatric research has become increasingly evident. Thus far, however, the literature has not provided the kind of information which is necessary if a psychiatric researcher wants to know how to proceed in actually planning and designing computer simulation experiments on systems which differ from the special cases cited in the literature. On the other hand, there is no shortage of technical articles or monographs dealing with certain specific problems related to computer simulation such as the generation of pseudorandom numbers