We conducted this review to determine whether U.S. Customs and Border Protection (CBP) has implemented the Department of Homeland Security’s (DHS) Prison Rape Elimination Act of 2003 (PREA) regulations. The DHS PREA regulations set standards for CBP to prevent, detect, and respond to sexual abuse and assault. The regulations also require CBP to complete audits of holding facilities that “house detainees overnight” by July 2018. Since DHS issued its PREA regulations, CBP has taken measures, including issuing its zero-tolerance policy and designating a full-time Prevention of Sexual Assault Coordinator, to ensure its offices, stakeholders, and managers are aware of CBP’s roles and responsibilities. However, CBP’s implementation actions lack adequate planning, a budget, a component-wide policy to coordinate the efforts of all offices and personnel, and criteria to determine which facilities should be defined as overnight facilities and therefore subject to audits. Further, at the time of our review, CBP had not determined the feasibility of securing a joint PREA audit contract with U.S. Immigration and Customs Enforcement. These problems may hinder CBP’s implementation of the DHS PREA regulations and ultimately, its ability to meet PREA’s goal to prevent, detect, and respond to sexual abuse and assault.