Jacques Paul Klein is a retired United States diplomat, who served as head of three United Nations peacekeeping missions: the United Nations Transitional Administration for Eastern Slavonia (UNTAES) from 17 January 1996 to 1 August 1997, the United Nations Mission in Bosnia and Herzegovina (UNMIBH) from 16 July 1999 to the 31 December 2002, and the United Nations Mission in Liberia (UNMIL) from 17 July 2003 to 20 July 2005.