Henry DeWolf Smyth (1898-1986) was an American physicist, diplomat, and bureaucrat.
During World War II, Smyth was a member of the National Defense Research Committee’s Uranium Section, producing fissile material for the bomb. He also proposed the electromagnetic methods that were used to enrich the first samples of U-235 during the Manhattan Project. Smyth worked as a consultant for the Manhattan Project from 1943 to 1945 and served as an associate director of the University of Chicago’s Metallurgical Laboratory.
Smyth was also appointed by General Leslie Groves to the Postwar Policy Committee, to propose government policy for research and development of atomic energy after the war in 1944. He also wrote a comprehensive report on the bomb, released after its use. The report became known as the Smyth Report and was widely disseminated throughout the country.