Heraldo Muñoz Valenzuela (born July 22, 1948) is a Chilean politician and diplomat, the former Chilean Ambassador to the United Nations, and currently Assistant Secretary General, Assistant Administrator, and Regional Director for Latin America and the Caribbean of the United Nations Development Programme.
Muñoz was born in Santiago. In 1973, under the Salvador Allende government, he served as National Supervisor of the People's Stores (Almacenes del Pueblo) until the coup d'état of September 11, 1973. He holds a Ph.D. from Josef Korbel School of International Studies at the University of Denver, Colorado (1978), a Diploma in International Relations from the Catholic University of Chile (1975, graduated with honors), and also took courses at Harvard University. He received a B.A. with a major in Political Science at the State University of New York, Oswego. Recipient of the "Distinguished Alumnus Award" from the Graduate School of International Studies at the University of Denver (1991), he was bestowed with the title of Doctor Honoris Causa from the State University of New York (1996). He has received fellowships from: Resources for the Future, the Ford Foundation, the Tinker Foundation, the Twentieth Century Fund, and the MacArthur Foundation. He was a Ph.D. fellow at the Brookings Institution, Washington, D.C. (1977). He later taught at the University of Chile's Institute of International Studies.
He co-founded the Party for Democracy (PPD) and participated in the executive committee of the campaign to vote "no" on a second term for Augusto Pinochet during the 1988 plebiscite. During the administration of Patricio Aylwin, Muñoz was made permanent representative for Chile to the Organization of American States, (1990-1994) and ambassador to Brazil (1994-1998) during the government of Eduardo Frei Ruiz-Tagle. At the start of the administration of Ricardo Lagos, Muñoz was appointed Deputy Minister of Foreign Relations until January of 2002, when he was designated Minister Secretary General of Government, a position from which he exercised considerable influence over policy, advising Lagos. He left the ministry in 2003, after being appointed Chile's ambassador to the United Nations, Permanent Representative. In May 2010, Muñoz was designated by UN Secretary General Ban Ki Moon as Assistant Secretary General, Assistant Administrator, and Regional Director for Latin America and the Caribbean of the United Nations Development Programme.