Little is known about contemporary physicians' sense of preparedness for bioterrorism, willingness to treat patients despite personal risk, or belief in the professional duty to treat during epidemics. In a recent national survey few physicians reported that they or their practice are "well prepared" for bioterrorism. Still, most respondents reported that they would continue to care for patients in the event of an outbreak of "an unknown but potentially deadly illness," although only a narrow majority reported believing in a professional duty to treat patients in epidemics. Preparing physicians for bioterrorism should entail providing practical knowledge, preventive steps to minimize risk, and reinforcement of the profession's ethical duty to treat.