['Applications to cardiothoracic training programs have declined dramatically. Increased effort in recruiting trainees is paramount. In this study, we test our hypothesis that mentored instruction on cardiothoracic simulators will enhance the interest of junior medical students in cardiothoracic surgery.', 'First- and second-year medical students were recruited from a "surgery interest group" to receive mentored instruction on high-fidelity cardiothoracic simulators. Before and after simulation assessment tools were used to assess attitudes toward simulation, general surgery, and cardiothoracic surgery.', 'Forty-four medical students participated in the study. Although 80% of the students were interested in pursuing a career in surgery before the course, the majority (64%) indicated they were "neutral" about pursuing a career in cardiothoracic surgery. After participating in the course, 61% of the students agreed or strongly agreed that they were interested in pursuing a career in cardiothoracic surgery (p = 0.001). When asked to select a surgical subspecialty for their third-year clerkship rotation, 18% of the students selected thoracic surgery before participating in the simulator course versus 39% after completing the course. This increase was most evident among the female participants, of whom only 3 (12%) selected a thoracic rotation before the simulator course versus 9 (35%) after completion of the course (p < 0.05).'] Does simulation experience enhance medical students ' interest in cardiothoracic surgery?