Assistant engineer Western Electric Company, 1930-1931. Instructor mathematics Swarthmore College, 1931-1933. Benjamin Pierce instructor mathematics Harvard, 1936-1938.
Associate professor mathematics Kenyon College, 1938-1941, professor mathematics, 1941-1947, department chairman, 1945-1947. Science liaison officer London mission Office of Scientific Research and Development, American embassy, 1944-1946, head of mission, 1945-1946. Science director London branch office, United States Office Naval Research, 1946-1948.
Chief, fundamental research branch, div. of research Atomic Energy Commission, Washington, 1948-1949. Executive director American Mathematics Society 1949-1954. Part time research associate Brown U. 1951-1954.
Professor mathematics, department chairman Washington University, St. Louis, 1954-1961. Professor mathematics Case Institute Technology, Cleveland, 1961-1974, department chairman, 1961-1963.
Fellow of the American Association for the Advancement of Science (council 1964). Member Mathematics Association American (member commission on educational media 1962-1966, chairman 1962-1963, governor 1966-1969, visiting lecturer 1958-1974), Society for Industrial and Applied Mathematics (council 1961-1964), London, Indian mathematics societies, Societe Mathematique de France, Phi Beta Kappa, Sigma Xi.