The following article is the third in a series of eight, which together constitute the report of a two and one-half year Survey of Postgraduate Medical Education by the Council on Medical Education and Hospitals of the American Medical Association. The survey included a questionnaire study of a large random sample of practicing physicians as well as detailed analyses of the postgraduate courses offered by the numerous sponsoring institutions and organizations. The first and second articles in this series, entitled "Scope and Extent of Postgraduate Medical Education" and "The Physician as a Lifelong Student," appeared In the Feb. 26,1955, and March 12,1955, issues of The Journal, pages 703 and 912 respectively. Postgraduate medical education Is an extension of the training of a physician beyond his undergraduate and graduate years. The early years of school and hospital training provide a basis for understanding human biology as well as disease and the