Childhood and early education in New York, undergraduate education in philosophy at Columbia College, 1932-1936; years of graduate study in physics at Columbia University, 1936-1937; influence of Isidor I. Rabi, the joint NYU-Columbia seminar in physics; transfer to Cornell University for graduate work in nuclear physics, 1937-1939; influence of Hans Bethe; thesis work on white dwarfs; first teaching position at University of Rochester, joint work with Victor Weisskopf in nuclear physics and particles; remarks on war years, astrophysics, cyclotrons, and other matters; Shelter Island Conferences. Formation of the Federation of American Scientists (F.A.S.) in 1946; Marshak succeeds Robert Wilson as Chairman, 1947. World Federation of Scientific workers, chaired by Frďřic Joliot-Curie, wants to enroll F.A.S. (1947, in Paris meeting). Marshak's work on two-meson theory. F.A.S. issues in the 1950s; the Emergency Committee and F.A.S.; Einstein's interests and views on relation of science to society; comments on J. Robert Oppenheimer; chairmanship at University of Rochester; Lee DuBridge; long-range plan and extensive development of physics department funded through AEC contracts; training of students from abroad such as Okubo, Sudarshan, Messiah, Regge. Last half of interview covers the Rochester conferences. Scientific work during the 1950s, the V-A interaction (George Sudarshan) theory (a.k.a. Feynman-Gell-Mann theory of weak interactions); books and works with graduate students. Travels to Europe and India (Tata Institute), 1953. Accepts City College (CUNY) presidency; reasons for leaving University of Rochester. Also prominently mentioned are: Robert Fox Bacher, Subrahmanyan Chandrasekhar, George Braxton Pegram, Julian R. Schwinger, Edward Teller; Lawrence Radiation Laboratory, and Massachusetts Institute of Technology Radiation Laboratory.