The collection includes personal papers, pocket diaries, photographs, literary material and personal correspondence.

There is only a small amount of material relating to HMB's early life and unfortunately a great many papers and correspondence were destroyed in a German bombing raid on London during the Second World War. Virtually all HMB's letters home written as a prisoner-of-war (BLGN 3) appear to have survived and constitute an interesting record of his experiences during the Second World War (though the letters were subject to British and German censorship only one letter was been emasculated by the censors) and it appears that the Germans treated their prisoners quite well - at any rate in the two camps in which HMB was incarcerated for 3 years (see BLGN 3/6-7). The collection also includes a section (BLGN 6) relating to the war crimes trials which took place after the Second World War.

Copies of HMB's typescripts and in some cases of his proofs or prints of his articles are found in BLGN 5/1-11. Drafts of planned short stories, books and novels which were not completed are found in BLGN 11/1-7.

This collection has an 'Associated' section, consisting of material from one or more sources distinct from the main series, potentially including material about, but not created, accumulated or owned by, the subject of the collection.