UNRISD
United Nations Research Institute for Social Development
UNRWA
United Nations Relief and Works Agency for Palestine Refugees in the
Near East
UNSC
United Nations Security Council
UNSSC
Untied Nations System Staff College
UNTSO
United Nations Truce Supervision Organization
UNU
United Nations University
UNWTO
World Tourism Organization
UPU
Universal Postal Union
US
United States
USSR Union of Soviet Socialist Republics (Soviet Union); used for information dated before 25 December 1991