The United Nations Secretariat is the executive body of the United Nations. It has the primary responsibility for the maintenance of international peace and security. The head of the Secretariat is the Secretary-General of the United Nations, who is appointed by the United Nations General Assembly.
United Nations Secretariat
Offices and departments
In addition to the New York headquarters, the United Nations maintains the following field offices of the UN Secretariat:
- United Nations Office at Geneva (UNOG)
- United Nations Office at Vienna (UNOV)
- United Nations Office at Nairobi (UNON)
The activities of the UN Secretariat are divided among the following departments:
| Executive Office of the Secretary-General | EOSG | Executive Office of the Secretary-General |
| Office of Internal Oversight Services | OIOS | Office of Internal Oversight Services |
| Legal affairs | OLA | Office of Legal Affairs |
| Political Affairs and Peacebuilding Department | DPPA | Department of Political and Peacebuilding Affairs |
| Office for Disarmament Affairs | ODA | Office for Disarmament Affairs |
| Department of Peacekeeping Operations | DPO | Department of Peace Operations |
| Operational Support Department | DOS | Department of Operational Support |
| UN Office for the Coordination of Humanitarian Affairs | OCHA | Office for the Coordination of Humanitarian Affairs |
| Counterterrorism Bureau | OCT | Office of Counter-Terrorism |
| Department of Economic and Social Affairs | DESA | Department of Economic and Social Affairs |
| General Assembly and Conference Management Department | DGACM | Department for General Assembly and Conference Management |
| Press and Information Department | DPI | Department of Public Information |
| Management Strategy, Policy and Compliance Department | DMSPC | Department of Management Strategy, Policy and Compliance |
| Office for Information and Communication Technology | OICT | Office of Information and Communications Technology |
| Office of the High Representative for Least Developed Countries, Landlocked Developing Countries and Small Island Developing States | OHRLLS | Office of the High Representative for Least Developed Countries, Landlocked Developing Countries and Small Island Developing States |
| Office of the United Nations Security Coordinator | UNSECOORD | Office of the United Nations Security Coordinator |
| UN Office for Disaster Risk Reduction | UNDRR | United Nations Office for Disaster Risk Reduction |
| UN Office on Drugs and Crime | UNODC | UN Office on Drugs and Crime |
The departments in the UN Secretariat are headed by an Under-Secretary-General of the United Nations (USG).
Secretaries-General of the UN (chronological)
(→Compare the list of Secretaries General and Deputy Secretaries General)
- 1946-1952: Trygve Lie (Norway)
- 1953-1961: Dag Hammarskjöld (Sweden)
- 1961-1971: Sithu U Thant (Burma)
- 1972-1981: Kurt Waldheim (Austria)
- 1982-1991: Javier Pérez de Cuéllar (Peru)
- 1992-1996: Boutros Boutros-Ghali (Egypt)
- 1997-2006: Kofi Annan (Ghana)
- 2007-2016: Ban Ki-moon (Republic of Korea)
- since 1 January 2017: António Guterres (Portugal)