The publication of the Organ Procurement and Transplantation Network (OPTN) Final Rule in 2000 resulted in a new and different regulatory environment for solid organ transplantation in the United States. In this review the role of the OPTN in providing oversight is clarified, differentiating the powers of enforcement the OPTN and HHS possess compared to the importance of confidential peer review in promoting compliance with OPTN policies. The function of the OPTN's Membership and Professional Standards Committee (MPSC) in adjudicating center performance and investigating alleged violations is described as well as the type and impact of adverse actions that the MPSC can recommend. The role of the OPTN Board compared to that of the Secretary of HHS in determining adverse actions is differentiated. We describe MPSC's broad scope of work in the ongoing evaluation of performance of all transplant centers. Finally, the relationship between the OPTN oversight and other entities charged with safe health care practices in the United States is considered.