This paper discusses a methodology for psychological instrumentation in which requirements common to a spectrum of experiments are defined and implemented in a microcomputer system. The microcomputer may either stand alone or be used as an intelligent front end to a larger computer. In either case, experiments are described in a high-level implementation language. The advantages of this approach include reduced hardware and maintenance costs, increased reliability, and smoother operation by research personnel. A tutorial example is given of the design and construction of one such system used to present visual stimuli, including text, graphics, and simple animation, on a movable array of video monitors. Displays are produced by a Z80 microcomputer in response to commands from a larger host computer, in this case a PDP Lab/8e. Illustrations are given of three studies in progress; comparisons are made with special-purpose equipment built earlier. The microcomputer system is preferable from both a cost and management point of view.