This paper analyzes and synthesizes the literature on primary care specialty choice from 1987 through 1993. To improve the validity and usefulness of the conclusions drawn from the literature, the authors developed a model of medical student specialty choice to guide the synthesis, and used only high-quality research (a final total of 73 articles). They found that students predominantly enter medical school with a preference for primary care careers, but that this preference diminishes over time (particularly over the clinical clerkship years). Student characteristics associated with primary care career choice are: being female, older, and married; having a broad undergraduate background; having non-physician parents; having relatively low income expectations; being interested in diverse patients and health problems; and having less interest in prestige, high technology, and surgery. Other traits, such as value orientation, personality, or life situation, yet to be reliably measured, may actually be responsible for some of these associations. Two curricular experiences are associated with increases in the numbers of students choosing primary care: required family practice clerkships and longitudinal primary care experiences. Overall, the number of required weeks in family practice shows the strongest association. Students are influenced by the cultures of the institutions in which they train, and an important factor in this influence is the relative representation of academically credible, full-time primary care faculty within each institution’s governance and everyday operation. In turn, the institutional culture and faculty composition are largely determined by each school’s mission and funding sources—explaining, perhaps, the strong and consistent association frequently found between public schools and a greater output of primary care physicians. Factors that do not influence primary care specialty choice include early exposure to family practice faculty or to family practitioners in their own clinics, having a high family medicine faculty-to-student ratio, and student debt level, unless exceptionally high. Also, students view a lack of understanding of the specialties as a major impediment to their career decisions, and it appears they acquire distorted images of the primary care specialties as they learn within major academic settings. Strikingly few schools produce a majority of primary care graduates who enter family practice, general internal medicine, or general practice residencies or who actually practice as generalists. Even specially designed tracks seldom produce more than 60% primary care graduates. Twelve recommendations for strategies to increase the proportion of primary care physicians are provided.