Correspondence relating to Peierls's editing of and contribution to Vol. 9 (Nuclear Physics) of Bohr's collected works (North Holland, 1986). Conducted principally with E. Rüdinger (Series Editor) and with A. Bohr, but also with colleagues and historians sending information and recollections. Peierls made several extended visits to the Niels Bohr Institute, Copenhagen while the work was in progress. Includes list, taken from the Institute's guest book, of visits by Peierls and by G. Placzek, 1930-1947.