The objective of this study was to ascertain how much U.S. medical students are taught about and know about military medical ethics, the Geneva Conventions, and the laws governing conscription of medical personnel. The authors developed an Internet-based questionnaire on these matters, and e-mail invitations to participate were sent to approximately 5,000 medical students at eight U.S. medical schools. Thirty-five percent of e-mail recipients participated in the survey. Of those, 94 percent had received less than one hour of instruction about military medical ethics and only 3.5 percent were aware of legislation already passed making a "doctor's draft" possible; 37 percent knew the conditions under which the Geneva Conventions apply; 33.8 percent did not know that the Geneva Conventions state that physicians should "treat the sickest first, regardless of nationality;" 37 percent did not know that the Geneva Conventions prohibit ever threatening or demeaning prisoners or depriving them of food or water; and 33.9 percent could not state when they would be required to disobey an unethical order.