This study describes the evolution of specialty choices among US medical school seniors in 1983 and 1987. Its purposes were to determine the specialty interests of the 1987 cohort as these 11,264 students proceeded through medical school and to compare their evolving specialty plans with those of the 10,321 US medical school seniors in 1983. As the 1987 cohort advanced through medical school, they became increasingly interested in general and subspecialty internal medicine, psychiatry, obstetrics and gynecology, anesthesia, radiology and rehabilitation medicine and less interested in family practice, general surgery, pathology, and public health. Compared with the 1983 cohort, 1987 seniors were significantly less likely to choose general internal medicine and more likely to choose internal medicine and pediatric subspecialties. Similar proportions of each cohort of seniors chose family practice. Between 1983 and 1987, men's interest in pediatrics, general surgery, and obstetrics and gynecology declined, while their interest in the surgical subspecialties, anesthesia, and rehabilitation medicine increased.