In the setting of world population growth and migration, global health issues have an increasing impact on domestic conditions and our medical practitioners. The authors ask: What exactly constitutes global health, and how much do U.S. and Canadian medical students or practitioners need to know about it? To address this topic, the authors convened an American Society for Tropical Medicine and Hygiene Committee on Medical Education, sought input from the Global Health Education Consortium, and surveyed members of the American Committee on Clinical Tropical Medicine and Travelers' Health for educational priorities within the tropical medicine field. The information gained from these sources has been distilled into three domains of global health competency that the authors propose each medical school curriculum should try to achieve for all students: global burden of disease, traveler's medicine, and immigrant health. The authors present here the rationale for altering curricula to include these three topics as a starting point for discussion among medical educators.