A relatively simple computer-based information system developed for a primary care group practice at the San Francisco Veterans Administration Hospital contributes to the management of the practice, to improvement of medical care for patients within the group, and to research studies on resource utilization in the management of chronic diseases and the evaluation of care of chronically ill patients. Preliminary results from the use of the information system are encouraging and demonstrate that much may be achieved by information systems that do not attempt to computerize the entire medical record.