Mr. António Guterres, the ninth Secretary-General of the United Nations, took office on 1 January 2017. His predecessors were:

• Ban Ki-moon (Korea), who held office from January 2007 to December 2016;
• Kofi A. Annan (Ghana), who held office from January 1997 to December 2006;
• Boutros Boutros-Ghali (Egypt), who held office from January 1992 to December 1996;
• Javier Pérez de Cuéllar (Peru), who served from January 1982 to December 1991;
• Kurt Waldheim (Austria), who held office from January 1972 to December 1981;
• U Thant (Burma, now Myanmar), who served from November 1961, when he was appointed acting Secretary-General (he was formally appointed Secretary-General in November 1962) to December 1971;
• Dag Hammarskjöld (Sweden), who served from April 1953 until his death in a plane crash in Africa in September 1961; and
• Trygve Lie (Norway), who held office from February 1946 to his resignation in November 1952.

Although there is technically no limit to number of five-year terms a Secretary-General may serve, none so far has held office for more than two terms.