Universal Postal Union

Universal Postal Union, specialized agency of the United Nations, consisting of 189 member states and territories united in a single postal territory for the reciprocal exchange of correspondence. Nearly all independent nations and various dependent territories are members. The union implements the provisions of the Universal Postal Convention, adopted in 1874, which specifies the types of correspondence that may be transmitted internationally; prohibits mailing of certain articles and commodities, such as narcotics; provides for the redirection or return of correspondence that cannot be delivered; regulates payments when the mail goes through the territory of several members; and guarantees freedom of transit throughout the entire union.

The organization was established in 1875 as the General Postal Union by the provisions of the convention; the present name was adopted in 1878. In 1947 the union became a specialized UN agency, responsible for international postal activities. Headquarters is in Bern, Switzerland.