Universal Postal Union

The Universal Postal Union, established by the Treaty of Bern of 1874, is a specialized agency of the United Nations that coordinates postal policies among member nations, in addition to the worldwide postal system. The UPU contains four bodies consisting of the Congress, the Council of Administration, the Postal Operations Council and the International Bureau. It also oversees the Telematics and Express Mail Service cooperatives. Each member agrees to the same terms for conducting international postal duties. The UPU's headquarters are located in Bern, Switzerland.

Source: Wikipedia