The International Astronomical Union (IAU) is the leading world organization for astronomers, founded in 1919. With over 9,200 individual members and 64 national members, the IAU plays a pivotal role in promoting and coordinating worldwide cooperation in astronomy. It also serves as the internationally recognized authority for assigning designations to celestial bodies and any surface features on them. The scientific and educational activities of the IAU are organized by its 12 Scientific Divisions and, through them, its 40 more specialized Commissions covering the full spectrum of astronomy, along with its 71 Working and Program Groups. The long-term policy of the IAU is defined by the General Assembly and the focal point of its activities is the permanent IAU Secretariat at Institut d'Astrophysique in Paris, France.