Includes: a long correspondence with Conrad Russell (many of Lady Diana's letters being in diary form); love letters between her and Windham Baldwin; letters from Lady Diana to her family; general correspondence, particularly with Duff Cooper's nephew Rupert Hart-Davis; letters of condolence on Duff's death; correspondence between Lady Diana and her son John Julius Cooper (her letters frequently turning into diary entries, taking up from where the diary letters to Conrad Russell leave off in 1947).