There is a projected shortage of primary care physicians in the United States, and providers other than U.S medical graduates may be needed to fill the gap. The authors conducted this study to quantify the contribution that Caribbean-educated physicians make to the U.S. primary care workforce. Using May 2011 American Medical Association Physician Masterfile and Educational Commission for Foreign Medical Graduates data, the authors identified physicians whose Masterfile records indicated that they provided direct patient care. They classified these physicians according to the type of medical school from which they graduated: graduates of Caribbean medical schools (C-IMGs), graduates of other international medical schools (non-C-IMGs), graduates of U.S. MD-granting medical schools (USMGs), and graduates of U.S. DO-granting medical schools (DOs). They then calculated the frequencies and percentages of self-designated primary care specialties for each physician classification. There were 684,469 physicians in direct patient care categories for whom data were available concerning medical school and self-designated specialty. About one-quarter of these physicians were graduates of international medical schools (C-IMGs: 3.0%, n = 20,333; non-C-IMGs: 20.4%, n = 139,415), and approximately three-quarters were U.S. medical school graduates (USMGs: 70.3%, n = 481,061; DOs: 6.4%, n = 43,660). Overall, C-IMGs had the highest proportion of physicians practicing in primary care specialties (56.7%) compared with non-C-IMGs (42.3%), USMGs (32.9%), and DOs (54.0%). More than half of Caribbean-educated physicians involved in direct patient care are practicing in primary care specialties, thereby making an important contribution to the U.S. primary care workforce.