Natural history diaries, 1935-1998, field notes, 1952-1994, typescript and published articles, 1947-1998, notes and correspondence relating to his books, 1933-1998, and to various natural history and historical subjects, card indexes, 1930-1998, and printed pamphlets, papers and books relating to Henry Thoreau, 1943-1999. There are several files of general personal correspondence, 1938-2016, including letters from R.S. Thomas. Inevitably, there are considerable overlaps between the various subsections of the archive, since Condry's interests, professional duties and literary activities were inextricably linked. Additional correspondence and papers, 1948-2020, including the files of letters from R. S. Thomas and his wife Mildred Elsie Eldridge (Elsi), 1968-1998, were transferred to NLW in December 2015, May 2018 and June 2020; a further letter, [c. 1946], by William Condry to Ray Perry, was donated in January 2016; a letter by Condry to his niece, Christine Demmar, enclosing a story about a pet jackdaw, was donated in August 2016; and transcript of a speech given by Chris Fuller at the opening of the William Condry centenary exhibition at MOMA, Machynlleth, in September 2018., donated in October 2018.