This series contains original letters to Barker and typescript carbon copies or photocopies of letters from him. Much of the correspondence is with authors and prospective authors. A few letters relate to Barker's investment in the Collector Ltd. Interfiled with Barker's correspondence are some letters to and from others on the editorial staff, including David McKitterick, John Commander, and chiefly Joan Stevenson (1966-ca. 1979). Some letters to and from her include proofs of articles.