Historically, clinical, research and administrative functions were carried out by independent computer-based medical systems. Even today, clinical and health care systems often remain separated by boundaries between medical sub-specialties. They are based on different application software packages and are built on different computer platforms. Success in development of electronic medical record depends, in large part, on progress in linking and integration of existing systems in medicine and health care. We were successful in integrating various systems using desktop tools, LAN, and mainframe interfaces. This allowed us to obtain useful scientific results, reduce administrative expenses and increase overall productivity.