The long-term research objective is to make commercially available a microcomputerbased system to facilitate patient self-control of insulin dependent diabetes mellitus. This comprehensive "Diabetes in Self-Control (DISC) System" is composed of (1) an instructional and reinforcement component for computer-assisted home bloodglucose monitoring; (2) a component which provides computer-assisted instruction (CAI) on the influence of patient behavioral variables upon both general and a specific, individual subject's glycemic control; and (3) a diabetes problem-solving component. During Phase I, ten adolescent subjects will proceed through all of the described DISC components, DISC subject scores on measures of glycemic control and diabetes knowledge will be compared with scores of ten subjects who will follow a conventional education (CE) program. It is hypothesized that the DISC subjects will demonstrate more improvement in diabetes knowledge and in metabolic control than will the CE subjects. A larger-scale evaluation including adult and adolescent subjects and incorporating additional factors will be conducted in Phase II. The DISC system will constitute a major advance over the traditional diabetes education and other computer-assisted diabetes management approaches. The DISC system is innovative in its focus on increasing subjects' internal motivation and problem-solving abilities which are crucial processes in comprehensive diabetes self-control.