U.S. federal regulations governing the protection of human subjects in research have been in existence for more than 30 years. The Department of Health, Education, and Welfare first published regulations for the protection of human subjects in 1974, and the Department of Health and Human Services (HHS) revised them in the early 1980s. To promote uniformity, understanding, and compliance with human subject protections, U.S. federal departments and agencies adopted the revised version of the regulations in 1991; subpart A of 45 Code of Federal Regulations (CFR) part 46 was created. This is often referred to as the “Common Rule” or “Protection of Human Subjects Regulations”.