Digital computer-controlled environmental test systems, originally developed for random vibration testing, can also be used for sine-wave testing, for large-scale time series analysis and presentation, for simulated natural environment testing (for example, temperature, pressure, and humidity), and for related applications. Costs and requirements for such systems are discussed; costs level off with multiapplications. Organizational changes, in both personnel and plant facility, must be considered. Additional development and modification of the control logic programs is an important capability after delivery. Control loop speed constraints are considerations for real-time test control. Tradeoffs must be made for the input-output devices and word storage. Reliability maintainability, and personnel training are important parameters that are also discussed.