Natural radioactivity; ideas of nuclear constitution, size in 1920s; Gamow-Condon-Gurney theory of alpha decay 1928; discovery of neutron 1932; Cambridge as a center of research 1933; early theories of nuclear forces; analysis of short-range nuclear forces 1935-40; reasons for writing Rev. Mod. Phys. review articles 1935-37 and detailed review of articles' contents; beta decay and the neutrino hypothesis; application of group-theoretic methods to nuclear physics 1936-37; compound nucleus model 1936; nuclear models in general (compound nucleus, evaporation, liquid drop, direct interaction, statistical); contemporary knowledge of nuclear physics 1938-39; stellar energy production; energy limit on cyclotron; accelerators and theoreticians; nuclear physics at Los Alamos; post-war conferences; origins and development of the shell model of the nucleus; many-body theory in nuclear physics; current algebras in particle physics; origins and development of the optical model; of the collective model; autobiographical comments on political, social, scientific conditions in Germany and England in early 1930s ; nuclear studies at Cornell after the war; building the H-bomb; the Oppenheimer hearings; work as a consultant 1950-1970; involvement with PSAC 1956; views on disarmament; receipt of 1967 Nobel Prize.