BACKGROUND Trends in career choice among specialties have varied greatly. Most notable is the recent decrease in the percentage of US medical student graduates choosing a primary care career, which has important implications for the US physician workforce. OBJECTIVE To review temporal trends in career choice by graduates of allopathic US medical schools, focusing on US medical doctors entering residencies since 1987. METHODS Three databases, the Association of American Medical Colleges Graduation Questionnaire (AAMC GQ), the National Resident Matching Program, and the national Graduate Medical Education census, were used to review temporal trends in the number of US medical doctors entering residencies in primary care, general or subspecialty surgical, and non-primary care and nonsurgical specialties from 1987 to 2002. RESULTS In 1987, 49.2% of all medical school graduates matched to one of the generalist residencies (internal medicine, pediatrics, or family medicine). The percentage of students matching to primary care specialties declined in the early 1990s, peaked at 53.2% in 1998, and declined to 44.2% in 2002. Concurrent with the latter decline, AAMC GQ data showed a decrease in medical student interest in primary care careers (35.6% in 1999 to 21.5% in 2002). The total percentage of US medical doctors matching to general or subspecialty surgical residencies remained stable at 11% to 12% from 1987 to 2002. During this same period, emergency medicine and plastic surgery increased as a match choice, while anesthesiology, pathology, and psychiatry were more variable over time. CONCLUSIONS Distribution of medical students' career choices among specialties varied considerably from 1987 to 2002. The debate will continue regarding the appropriate specialty mix within the physician workforce.