This collection consists primarily of letters received by Sitwell from 177 different correspondents, ranging from 1932 to 1964, but mostly between 1959 to 1961 when Sitwell lived in London at the Sesame Imperial & Pioneer Club. The correspondents include many friends, publishers, literary and business associates, family members and admirers. Various subjects discussed in the letters include family, social, and business news, and literary topics; and there are many get well wishes for Sitwell during an illness and after an accident. Some of the correspondents are Sylvia Beach, Bryher, Cyril Connolly, George Cukor, David Higham Associates, Alec Guinness, David Horner, John Lehmann, Ned O'Gorman, William Plomer, Georgia, Osbert,and Sacheverell Sitwell, Stephen Spender, Felix Topolski, and Beryl de Zoete.

Sitwell's writings in the collection include typescripts for a book review of John Brinnin's Dylan Thomas in America (1956), essays on various topics, such as "Charity," "Ezra Pound," and "On Genius," a few poems, and transcripts of radio and television interviews. Also present are financial papers, including bills and accounts presented to Sitwell from publishers, book stores, clubs, wine merchants, nurses, and other agents or businesses. Papers of others include a typescript of Henry Cecil's Portrait of a Judge and Other Stories (1964), and poems by Lilian Barnes, Tom Driberg, Thom Gunn, David Bulwer Lutyens, and Sacheverell Sitwell. There are also several of Sotheby's catalogs listing Sitwell items for auction and a large file of clippings about Sitwell and other topics.