With new tools derived from the Human Genome Project, genetic research is expanding from the study of rare, single gene disorders to the evaluation of genetic contributors to common, complex diseases. Many genetic studies include pediatric participants. The ethical concerns related to pediatric participation in genetic research derive from the study designs commonly employed in gene discovery and from the power accorded to genetic prediction in our society. In both family-based studies and large studies combining genetic and other health-related data, special attention should be placed on recruitment procedures, informed consent, and confidentiality protections. If data repositories are created for long-term use, we recommend re-consent of pediatric participants when they reach adulthood. In addition, the potential for disclosure of individual results should be considered as part of the institutional review of genetic studies, taking into account the validity of research data and the potential that such data could be used in health care. The potential for genetic results to pose harms of personal and group stigma is also a consideration. Because genetic information is often accorded special power in our society, careful attention should be paid to how genetic information is collected and used in research involving pediatric participants.