Chiefly letters to Shackle from other academic historians, from the publishers of his books, and from editors of journals, together with some copies of his replies. Shackle himself selected and arranged the letters. He had the earlier ones microfilmed before depositing the originals at Cambridge University Library. The correspondence listed here takes the form of photographic copies of the microfilms and the microfilms themselves. The original correspondence at Cambridge University Library is much more extensive and covers the years 1949-92.