Active exchange between theory, research, and application provides a rich environment for creative advances in sociology as well as in medicine. Medical sociology—a relatively new specialty within the social sciences—promises to contribute much to psychiatric research and practice. But the sociologist must learn to apply what he knows and to communicate with psychiatry without jargon. Both professions are cautioned against enthusiastic misapplication. Explaining the individual by describing his society is as misleading as explaining society by psychological mechanisms.