Computer services provided to the Navy Computer Managed Instruction (CMI) system and numerous non-CMI users are the focus of this report of a study designed to (1) analyze the response time, interruptions, and availability of the CMI system; (2) determine the impact of the non-CMI users on the ability of the system to respond to CMI requirements; and (3) identify the hardware/software limitations of the present CMI system and explore possible improvements. This report is designed for use in maintaining CMI system reliability, and provides data to support expansion of the system capability to serve an anticipated increase in the student load. An introduction is followed by a review and summary of the CMI performance data from March to October 1981; a description of the hardware and software configuration and limitations of the present system; a discussion of the requirements and problems associated with non-CMI users being served by the system; and an analysis of the relationship between computer downtime and training time to determine whether unavailability extends training time. A summary and recommendations conclude the report, and detailed information on various performance statistics is appended. (Author/LMM)