Recollections of physics community in 1920s and early 1930s; opportunities for physics work in Europe; awareness of political climate in Germany (1932); relationship with Werner Heisenberg at University of Leipzig; awarded Rockefeller Fellowship to study at University of Rome; contacts with physicists after Leipzig and before Rome; John Von Neumann's list of refugee physicists; offered appointment to position at Stanford University; visit to University of Copenhagen and Niels Bohr's advice to accept appointment; relinquishing of second half of fellowship; influenced by Bohr, Heisenberg and others; Bloch's influence on Enrico Fermi leading to theory of neutrino; met by Gregory Breit on arrival in New York; initial teaching duties at Stanford; theoretical physics in America in 1934; distinctions between Europe and America on theory vs. experiment; seminars with J. Robert Oppenheimer; first interest in experimental work; early research on neutrons; recollections of 1935 Michigan Summer School; started Stanford Summer School in 1936 with George Gamow as first visitor (Fermi 1937, Isidor Isaac Rabi 1938, Victor F. Weisskopf 1939); origin of idea of neutron polarization; 1936 paper proposing neutron magnetic moment experiment; 1937 Galvani Conference in Bologna; use of Berkeley 37-inch cyclotron for magnetic moment experiment; decision to build cyclotron at Stanford; construction supported by Rockefeller Foundation; initial involvement with Manhattan Project; recollections of receiving news of fission; neutron work for Manhattan Project at Stanford; marriage in 1940; work on implosion at Los Alamos Scientific Laboratory; reasons for leaving Los Alamos; work on radar at Harvard University; first ideas on measuring nuclear magnetic resonance (NMR); helpfulness of radar experience in NMR work; William W. Hansen and the klystron; fate of the first Stanford cyclotron; knowledge of Edward M. Purcell's work on NMR; publication of initial results, 1946-1948; Rabi and Polykarp Kusch's work on molecular beams; development of NMR field; Nobel Prize award; association with CERN, 1954; contributions of greatest impact.