The authors examined the impact of students' research involvement during medical school on their postresidency medical activities. The three medical schools involved--The Pennsylvania State University College of Medicine (PSU), The University of Connecticut School of Medicine (UCONN), and The University of Massachusetts Medical School (UMASS)--have nearly indistinguishable applicant, matriculant, and curriculum profiles. However, at PSU a research project is a curriculum requirement for students who did not do medical research prior to entering medical school. Questionnaires were sent to all graduates from the classes of 1980, 1981, and 1982. A total of 567 graduates completed the questionnaires, an overall response rate of approximately 76%. Medical school research experience was reported by 83% (183) of the PSU graduates, 34% (52) of the UCONN graduates, and 28% (54) of the UMASS graduates. When compared on a school-by-school basis, the graduates from the three schools did not differ with respect to residency specialty training, fellowship training, academic appointments, career practice choices, or postgraduate research involvement. However, when all the graduates studied were examined as a single group, medical school research experience was found to be strongly associated with postgraduate research involvement.