BACKGROUND: It has been found that physicians condone colleague involvement in capital punishment. Physicians' own willingness to participate has not been explored. OBJECTIVE: To examine physicians' willingness to be involved in cases of capital punishment. DESIGN: Survey exploring physicians' willingness to participate in 10 aspects of capital punishment by lethal injection, 8 of which are disallowed by the American Medical Association. SETTING: United States. PARTICIPANTS: 1000 randomly selected practicing physicians. MEASUREMENTS: Questions assessing willingness to be involved in and attitudes toward capital punishment. RESULTS: 41% of respondents indicated that they would perform at least one action disallowed by the American Medical Association; 25% would perform five or more disallowed actions. Perceived duty to society (P < 0.001), approval of the death penalty (P < 0.001), and approval of assisted suicide (P = 0.015) correlated with increased willingness to perform disallowed actions. Only 3% of respondents knew of any guidelines on this issue. CONCLUSIONS: Despite medical society policies, many physicians would be willing to be involved in the execution of adults. The medical profession needs to be better informed about the ethical issues involved in physician participation in capital punishment.