John Henry Sununu (born July 2, 1939) is an American politician who was the 75th Governor of New Hampshire (1983–1989) and later White House Chief of Staff under President George H. W. Bush. He is the father of John E. Sununu, the former United States Senator from New Hampshire, and Christopher Sununu, the current governor of New Hampshire. Sununu was the chairman of the New Hampshire Republican Party from 2009 to 2011.
Born in Havana, Cuba while his parents were visiting there, he grew up in New York City and graduated from the La Salle Military Academy on Long Island before earning B.S., M.S., and Ph.D. degrees in mechanical engineering from Massachusetts Institute of Technology. From 1963 until his election as governor, Sununu served as president of JHS Engineering Company and Thermal Research Inc. He was a mechanical engineering professor at Tufts University from 1966 to 1968 and associate dean of Tufts' College of Engineering until 1973. From 1973 to 1975, he represented Salem in the New Hampshire State Legislature.
Sununu became New Hampshire's 75th Governor on January 6, 1983, and was re-elected twice to hold the position for three consecutive terms. He was the first Arab-American Governor of New Hampshire. Sununu was chairman of the Coalition of Northeastern Governors, the Republican Governors Association and, in 1987, the National Governors Association. From 1984 to 1989, Sununu served on the Advisory Board of the Technology and Policy Program at MIT. On January 21, 1989, Governor Sununu was commissioned Chief of Staff to President George H. W. Bush, resigning on December 4, 1991; Sununu remained at the White House serving as Counselor to the President until March 1, 1992.
After leaving the White House, Sununu co-hosted CNN's nightly Crossfire from March 1992 until February 1998. Sununu is President of JHS Associates, Ltd. and is a partner in Trinity International Partners, a private financial firm. He is also a member of Honorary Council of Advisors for U.S.-Azerbaijan Chamber of Commerce (USACC).