Publisher Summary This chapter focuses on issues commonly encountered by, or of concern to, investigators in the clinical research environment. These issues include those related to– informed consent for standard and research care, types of advance directives and other surrogate decision making requirements, the involvement of children in research, maintenance of adequate medical records, protection of confidentiality, liability of clinical researchers, conflicts of interest, and authorship and rights in data. The most predominant legal liability issue in clinical research relates to the presence or absence of adequate informed consent. Understanding of these legal issues in clinical research is very necessary.