Primarily correspondence (1921-1978) which documents his career from his discovery (with George Uhlenbeck) of the electron spin (1927), through his work as editor of THE PHYSICAL REVIEW (1950-1974) and editor-in-chief at the American Physical Society (APS) (1966-1974), to his post as visiting professor at the University of Nevada (1974-1978). The APS correspondence mostly concerns the editing and publishing of THE PHYSICAL REVIEW and PHYSICAL REVIEW LETTERS, including computer typesetting and other innovations. Other correspondence topics are atomic structure, cyclotrons, quantum theory, nuclear physics, spectroscopy, and his involvement with the American Philosophical Society and the Desert Research Institute. Also covers his work during World War II as scientific head of the ALSOS Mission, an American scientific intelligence combat unit whose main objective was to determine German progress in developing an atomic bomb, and the publication of his book, ALSOS. Additional materials include course lectures given at the University of Nevada; speeches on ALSOS and other subjects; reports on the work and attitudes of German scientists during the Nazi regime; research data from Brookhaven National Laobratory, Northwestern University, and the University of Michigan; Goudsmit's notebooks from lectures given by Paul Ehrenfest (University of Leiden, 1920s and undated) and by others; and undated research notebooks. Other areas of interest covered include Egyptology, criminology, World War II refugees, parapsychology, UFOs, and philately. Correspondents include: Robert F. Bacher, Gregory Breit, Leon Brillouin, Detlev W. Bronk, Walter and Martha Colby, Dirk Coster, Gerard Heinrich Dieke, Paul Ehrenfest, Enrico Fermi, George Gamow, Werner Heisenberg, Jaap Kistemaaker, John R. Kohn, Alfred Land,̌ Jonathan Logan, Wendell Mordy, Linus Carl Pauling, Harrison Randall, Paul Rosbaud, George Uhlenbeck, John H. Van Vleck, Joseph Weber, Friedwardt Winterberg, John Wulff, and Pieter Zeeman.