The mapping and sequencing of the human genome promises rapid growth in understanding the genetically influenced mechanisms that underlie human disease. To realize this promise fully, it is necessary to relate genetic information to clinical phenotypes. Genetic tissue banking in clinical studies provides opportunities to analyze the genetic contribution to variation in response to treatments. The challenges to progress are likely to come from the complex organizational, social, political, and ethical issues that must be resolved in order to put clinical and DNA bank information together. Concerns about subjects' rights, informed consent, privacy, and ownership of genetic material require attention in the development of DNA banks. In this paper we describe one approach to the solution of these problems that was adopted by one clinical trials group, the Department of Veterans Affairs Cooperative Studies Program.