Researchers, institutional review boards (IRBs), participants in human subjects research, and their families face an important but largely neglected problem — how should incidental findings (IFs) be managed in human subjects research. If researchers unexpectedly stumble upon information of potential health or reproductive significance, should they seek expert evaluation, contact the participant’s physician, tell the research participant, or respond with some combination? What should consent forms and the entire consent process say about how IFs will be handled in research? What should IRBs require?