The National Institutes of Health (NIH) have initiated a series of consensus development exercises that will take place during 1978 and 1979. The major purpose of these exercises or conferences is to make useful new knowledge concerning the prevention, detection, diagnosis, and treatment of major disease entities available to practicing physicians. In the normal course of events, a substantial time lag occurs between the development of new, valid information by the research community and its widespread application in the provision of medical care. In large measure, this delay is the result of a slow diffusion process that relies on medical journals, professional meetings, courses, textbooks, and interpersonal contacts and lacks, therefore, planned promotional guidance. Consequently some new interventions for the treatment of disease are applied too slowly while others may actually be used prematurely. The consensus development conferences will bring together experts in a specific field for the purpose of