Abstract
The paper is devoted to the MEDSET technology for development, deployment and support of information systems (IS) in clinical medicine and other poorly formalized subject domains. This technology supports all stages IS life-cycle: modelling, engineering, deployment, support and evolution. The focus of the paper is evolutionary nature of clinical IS. MEDSET allows IS to develop evolutionary along different "dimensions": the number of supported business-processes, the number of user functions, the number of users, the degree of formalization of data. The program component of MEDSET is based on Internet technologies, so IS build under MEDSET can be used in remote mode as well as locally. The development of EPR/NSI - electronic patient records systems for N.N.Burdenko Neurosurgical Institute (Moscow, Russia) is briefly described.