Despite remarkable progress, much remains unknown about the risks and benefits of genetic testing. No effective interventions are yet available to improve the outcome of most inherited diseases; negative test results might not rule out future occurrence of disease, and positive test results do not necessarily mean the disease will inevitably develop. In view of this uncertainty, the Working Group on Ethical, Legal, and Social Implications of Human Genome Research at the National Institutes of Health and Department of Energy created the Task Force on Genetic Testing. Comprising representatives of fifteen major stakeholders in genetic testing and five government agencies involved with testing, the task force was charged with reviewing genetic testing in the United States and making recommendations to ensure the development of safe and effective genetic tests. In Promoting Safe and Effective Genetic Testing in the United States the members of this task force present the conclusions of their study. They begin by describing general principles involved in genetic testing, including informed consent, testing of children, confidentiality, and discrimination. They describe methods and policies to ensure the safety and effectiveness of new genetic tests, including criteria for developing tests and ways of ensuring compliance with those criteria. They then discuss how to ensure the quality of laboratories that perform genetic tests, including the role of laboratory personnel and methods of monitoring laboratory performance. They show how health care professionals outside the field of genetics can better understand the uses of genetic testing, and offer suggestions for changes in these professionals' education and training. Finally, they offer a look at testing for rare inherited genetic disorders. Members of the Task Force: Neil A. Holtzman, M.D., M.P.H. Michael S. Watson, Ph.D., F.A.C.M.G. Patricia A. Barr David R. Cox, M.D., M.P.H. Jessica G. Davis, M.D. Stephen I. Goodman, M.D., M.Sc. Wayne W. Grody, M.D., Ph.D. Arthur L. Levin, M.D. J. Alexander Lowden, M.D., Ph.D. Patricia D. Murphy, Ph.D. Patricia J. Numan, M.D. Victoria O. Odesina, R.N., Sc.M., M.S. Nancy Press, Ph.D. Katherine A. Schneider, M.P.H. David B. Singer Steven Gutman, M.D., Muin J. Khoury, M.D., Ph.D. David Lanier, M.D. Linda R. Lebovic Jane S. Lin-Fu, M.D.