This chapter discusses the use and misuse of genetic information for social ends, issues that arise at the interface of medicine and other social institutions such as the law; and issues of privacy and control over information about one's genotype. It concentrates on criminal law. Clinicians are generally expected to maintain the confidentiality of health information. However, this duty is not absolute, and must in some situations be violated if other ethical obligations are to be met. Knowledge of an individual's genotype gives one some knowledge of the genotype of family members. The history of the eugenics movement demonstrates the danger of uncritical acceptance of constructs that contain social value judgments. There is nothing inherent in the study of behavioral genetics that should alter our concepts of personal responsibility or our respect for individual autonomy. But this knowledge, if not carefully employed, can be misused.