The International Astronomical Union (IAU) was founded in 1919. Its mission is to promote and safeguard the science of astronomy in all its aspects through international cooperation. Its individual members are professional astronomers all over the World, at the Ph.D. level or beyond and active in professional research and education in astronomy. However, the IAU maintains friendly relations also with organizations that include amateur astronomers in their membership. National Members are generally those with a significant level of professional astronomy. With now over 9,100 individual members and 70 National Members worldwide, the IAU plays a pivotal role in promoting and coordinating worldwide cooperation in astronomy. The IAU also serves as the internationally recognized authority for assigning designations to celestial bodies and any surface features on them.