The Privacy and Civil Liberties Oversight Board (PCLOB) is an independent executive agency mandated with monitoring the actions of the U.S. government on civil liberties and privacy interests. The board consists of five members, each appointed by the President and confirmed by the Senate.

In 2004, following recommendations by the National Commission on Terrorist Attacks Upon the United States (known as the 9/11 Commission), the PCLOB was established within the Executive Office of the President. The board was tasked with advising the President and other senior Executive Branch officials to ensure that concerns with respect to privacy and civil liberties are appropriately considered in the implementation of all laws, regulations, and executive branch policies related to efforts to protect the Nation against terrorism.

Following concerns that the PCLOB be empowered to exercise independent oversight, Congress reconstituted the board as an independent agency within the executive branch through the Implementing Recommendations of the 9/11 Commission Act, which was signed into law on August 6, 2007.