Thomas Maria Messer (February 9, 1920 – May 15, 2013) was the director of the Solomon R. Guggenheim Foundation, including the Solomon R. Guggenheim Museum in New York City and the Peggy Guggenheim Collection in Venice, Italy, for 27 years, a longer tenure than any of the city's major arts institutions' directors.Born and raised in Czechoslovakia, Messer became a U.S. citizen in 1944 and served in the U.S. Army in World War II.