Previous studies of reasons for choosing medical specialties have been restricted to one specialty or to surveys of medical students. Since some students change their specialties after medical school, the present authors surveyed the graduates of a medical college's classes of 1971 through 1982 in regard to their selection of a number of different specialties. Overall, factors related to the content of the specialty and to contact with patients were rated as the most important in choosing a specialty; the quality of the medical college educational program was rated as of intermediate importance and life-style and personal factors as of least importance. Thirteen percent of those surveyed made major changes in specialties after graduation, with more of them leaving than entering internal medicine, pediatrics, and family practice and more of them entering than leaving the hospital service specialties (such as radiology and pathology) and psychiatry. The reasons for these changes involved financial and life-style considerations, for example, working hours, location, and financial rewards of practice.