| Acronym |
Agency/Organization/Definition |
| UDEAC |
Union Douaniere de Economique de l'Afrique Centrale; see Central African Customs and Economic Union (UDEAC) |
| UN |
United Nations |
| UNAIDS |
Joint United Nations Programme on HIV/AIDS |
| UNAMSIL |
United Nations Mission in Sierra Leone |
| UNAVEM II |
United Nations Angola Verification Mission |
| UNCLOS |
United Nations Convention on the Law of the Sea, also known as LOS |
| UNCTAD |
United Nations Conference on Trade and Development |
| UNDOF |
United Nations Disengagement Observer Force |
| UNDCP |
United Nations Drug Control Program |
| UNDP |
United Nations Development Program |
| UNEP |
United Nations Environment Program |
| UNESCO |
United Nations Educational, Scientific, and Cultural Organizations |
| UNFICYP |
United Nations Force in Cyprus |
| UNFPA |
United Nations Fund for Population Activities; see UN Population Fund (UNFPA) |
| UNHCR |
United Nations Office of the High Commisioner for Refugees |
| UNICEF |
United Nations Children's Fund |
| UNICEP |
United Nations International Comparison Program |
| UNICOR |
Federal Prison Industries |
| UNICRI |
United Nations Interregional Crime and Justice Research Institute |
| UNIDIR |
United Nations Institute for Disarmament Research |
| UNIDO |
United Nations Industrial Development Organization |
| UNIFIL |
United Nations Interim Force in Lebanon |
| UNIKOM |
United Nations Iraq-Kuwait Observation Mission |
| UNITAR |
United Nations Institute for Training and Research |
| UNMEE |
United Nations Mission to Ethiopia and Eritrea |
| UNMIK |
United Nations Interim Administration Mission in Kosovo |
| UNMIL |
United Nations Mission in Liberia |
| UNMISET |
United Nations Mission of Support in East Timor |
| UNMOGIP |
United Nations Military Observer Group in India and Pakistan |
| UNMOVIC |
United Nations Monitoring, Verification, and Inspection Commission |
| UNOMIG |
United Nations Observer Mission in Georgia |
| UNOMOZ |
United Nations Operation in Mozambique |
| UNOMUR |
United Nations Observer Mission Uganda-Rwanda |
| UNOPS |
United Nations Office of Project Services |
| UNOSOM |
United Nations Operation in Somalia |
| UNPROFOR |
United Nations Protection Force |
| UNRISD |
United Nations Research Institute for Social Development |
| UNRWA |
United Nations Relief Works Agency for Palestine in the Near East |
| UNSC |
United Nations Security Council |
| UNSSC |
United Nations System Staff College |
| UNSCEAR |
United Nations Scientific Committee on the Effects of Atomic Radiation |
| UNTAC |
United Nations Transitional Authority in Cambodia |
| UNTSO |
United Nations Truce Supervision Organization |
| UNU |
United Nations University |
| UPU |
Universal Postal Union |
| USA |
United States Army |
| USACE |
United States Army Corps of Engineers |
| USAF |
United States Air Force |
| U.S.C. |
United States Code |
| USDA |
United States Department of Agriculture |
| USDOC |
United States Dapartment of Commerce |
| USGS |
United States Geological Survey |
| USMC |
United States Marine Corps |
| USSR/EE |
USSR/Eastern Europe |
