Few studies that examine the career decisions of medical students have been based upon theories of decision-making. Several theories were used by the present authors to study differences among first-year medical students in North Carolina who preferred family medicine and those who preferred other specialties. Responses by 358 first-year students to a career preferences questionnaire administered in the fall of their freshman year revealed that students who preferred family medicine were more interested than other students in using medicine as a tool to help people. They were equally persistent and thorough in their career decision-making, were at an earlier stage of decision-making, and had less concern with themselves compared with other students. Decision-making theory helps to explain the relationships found in earlier studies between students' characteristics and their specialty preferences. The results of the present study also may explain the reason for the decrease during medical school in the number of students who prefer family medicine as a career. Those results show that first-year medical students who prefer family medicine are at an earlier stage of the decision-making process than other first-year medical students.