The current system of human-subject-research oversight and protections has developed over the last 5 decades. The principles of conducting human research were first developed as the Nuremberg code to try Nazi war criminals. The 3 basic elements of the Nuremberg Code (voluntary informed consent, favorable risk/benefit analysis, and right to withdraw without repercussions) became the foundation for subsequent ethical codes and research regulations. In 1964 the World Medical Association released the Declaration of Helsinki, which built on the principles of the Nuremberg Code. Numerous research improprieties between 1950 and 1974 in the United States prompted Congressional deliberations about human-subject-research oversight. Congress's first legislation to protect the rights and welfare of human subjects was the National Research Act of 1974, which created the National Commission for Protection of Human Subjects of Biomedical and Behavioral Research, which issued the Belmont Report. The Belmont Report stated 3 fundamental principles for conducting human-subjects research: respect for persons, beneficence, and justice. The Office of Human Research Protections oversees Title 45, Part 46 of the Code for Federal Regulations, which pertains to human-subjects research. That office indirectly oversees human-subjects research through local institutional review boards (IRB). Since their inception, the principles of conducting human research, IRBs, and the Code for Federal Regulations have all advanced substantially. This paper describes the history and current status of human-subjects-research regulations.