A topic such as legal issues in clinical research is expansive and cannot be fully explored in a few hours or even a few days. An attempt has been made in writing this chapter to focus on issues commonly encountered by, or of concern to, investigators in the clinical research environment. Issues include those related to (1) informed consent for standard and research care, (2) types of advance directives and other surrogate decision-making requirements, (3) involvement of children in research, (4) maintenance of adequate medical records, (5) protection of confidentiality, (6) liability of clinical researchers, (7) conflicts of interest, and (8) authorship and rights in data. Although some of the discussion focuses on laws, regulations, and/or policies applicable at federal research institutions (e.g., the National Institutes of Health Clinical Center), this chapter should be useful to investigators in other working environments.