In the last few years, the development of new communications network architectures has permitted the design and deployment of computer-based distributed systems. Office automated systems and computerized manufacturing systems are some examples of such systems. In the medical environment, ' the use of current and emerging communications networks will make possible the deployment of distributed medical communications systems capable of providing remote medical care services to distant communities (telemedicine). In this paper, we present a study whose main objective has been to explore the use of multimedia communications technology for medical applications physically distributed among hospitals, that is to say an interhospital multimedia communications system. The design and development issues of a prototype are described as well as the results of an in-field trial. From the results of this trial, a performance study has been developed for evaluating the expected communications requirements of a large-scale configuration of the system. © 1992 IEEE