OBJECTIVE To verify that motivational concepts tested in other educational settings are relevant to understanding medical students' choice of a career in internal medicine. More specifically, to compare the effects of "facilitating students' interest" versus "controlling students' learning" as educational models during the internal medicine clerkship. METHODS An observational retrospective study of 89 fourth-year medical students. Structural equation modeling compared the two models statistically. METHODS Student choice of internal medicine residency. RESULTS Instructors who supported students' autonomy engendered in students greater feelings of competence and interest in internal medicine than did controlling instructors. Perceived competence further enhanced students' interest in internal medicine. In turn, interest predicted students' choosing an internal medicine residency. Overall, the facilitating students' interest model better explained students' choice of internal medicine than did the controlling students' learning model. CONCLUSIONS The results verify that the nature of the learning climate during the internal medicine clerkship is an important predictor of students' subsequent pursuit of internal medicine training. Instructors who teach in an autonomy-supportive manner enhance students' perceived competence and interest in internal medicine, which increases the likelihood they will select an internal medicine residency.