EVIDENCE THAT LAY PEOPLE FREQUENTLY misinterpret risk raises concerns for the ethical conduct of human research, which requires adequate disclosure, understanding, and appreciation of risk information. Review of the risk communication research literature suggests new directions for empirical research on human research ethics: Investigation is needed on how to best assess and improve potential and enrolled subjects' understanding of risk information. Preferences regarding the presentation of risk information and the effects of alternative presentation formats and decision aids on knowledge, trust, satisfaction, risk/benefit analysis, and perceptions of respectful treatment should be studied. Research is also needed on the effects of payment for research participation, the order in which study information is presented, and having one's own physician present risk information.