High Quality Content by WIKIPEDIA articles! The African Union (abbreviated AU in English, and UA in its other official languages) is an intergovernmental organisation consisting of 52 African states. Established on July 9, 2002, the AU was formed as a successor to the Organisation of African Unity (OAU). The most important decisions of the AU are made by the Assembly of the African Union, a semi-annual meeting of the heads of state and government of its member states. The AU's secretariat, the African Union Commission, is based in Addis Ababa, Ethiopia. During the February 2009 Union meeting headed by Libyan leader Muammar al-Gaddafi, it was resolved that the African Union Commission would become the African Union Authority.