The collection covers Pyman's career from 1937 until 1963 when he suffered a severe stroke which forced his retirement in 1964. The earliest papers date from Pyman's work with the Royal Tank Cadre in converting the 17/21 Lancers from a cavalry to an armoured regiment. There are also papers from Pyman's period as an instructor at the Staff College in Quetta, India, 1939-1941. Pyman was involved in the World War Two campaigns by the 8 Army in the Western Desert, in 1941 as General Staff Officer with 7 Armoured Div, 30 Corps and in 1942-1943 as Commander of the 3 Royal Tank Regiment, 10 Armoured Div, 30 Corps. The papers consist mostly of Pyman's assessments of lessons learned from the ongoing campaigns particularly with regard to tanks and armoured units. In 1944-1945 Pyman was Brigidier General Staff, 30 Corps, 2 Army in the Normandy landings and the invasion of Northern Europe, with particular responsibility for organisation and planning of the Rhine crossing and advance to the Baltic. This is reflected in the papers which largely consist of planning studies and reports for the operations involved, this section also contains maps used in the campaign. Pyman's next appointment was as Chief of General Staff, Allied Land Forces, South East Asia, 1945-1946 which is documented by a series of diaries which reflect the tasks faced by Pyman in this command including dealing with the build up of tension between newly liberated former colonies keen to assert their right for independence and the former colonial powers such as France and Netherlands. Pyman spent 1946-1949 as Chief of Staff, Middle East Land Forces and kept monthly diaries which form the bulk of this section of the collection. The diary entries and additional papers reflect the debate over policy in the Middle East in the British Government and Military command, they include detail on the British withdrawal from Greece, the problem of illegal Jewish immigrants and their internment in Cyprus, the end of the British mandate in Palestine and the the effect of this on relations between Britain with Egypt and the other Arab states and the subsequent Arab Israeli conflict. This section of the collection also contains correspondence between Pyman and Maj Gen Sir Miles Christopher Dempsey on personal matters and on the Middle East. There are also papers from Pyman's work at the Ministry of Supply as Director General of Fighting Vehicles, 1951-1953, Director of Weapons Development, War Office, 1955-1956 mostly brief diary entries and lecture texts. Pyman was also General Officer Commanding, British Army on the Rhine, 1953-1955 and General Officer Commanding, 1 British Corps, 1956-1958 and the papers relating to these commands consist mostly of lectures, reports and directives reflecting his interest in armoured divisions and training. There are some papers, mostly personal correspondence and press cuttings, from Pyman's final command as Commander-in-Chief Allied Forces Northern Europe in North Atlantic Treaty Organisation (NATO). The collection also contains correspondence relating to Pyman's role as Colonel Commandant of the Royal Tank Regiment and The Royal Armoured Corps and a series of letters covering the reorganisation of the Berks and Westminster Dragoons, of which he was Honorary Colonel. The rest of the collection consists of diaries, correspondence, speeches, writings including the draft copy and papers relating to his autobiography, some preparatory work on a history of the 2 Army and reference works. The collection also includes the Boer War diaries and other papers of Col James Redmond Patrick Gordon who commanded the 1 Cavalry Bde of the South African Field Force 1900-1901 which were given to Pyman by a friend.

Twelve detailed, narrative, manuscript diaries, Jan 1933-Aug 1936 and Jan 1938-Dec 1944 (with postscripts added in Jan and Sep 1945), including Pownall's time as Military Assistant Secretary, Committee of Imperial Defence, 1933-1935, Commandant, School of Artillery, Larkhill, Wiltshire, 1936-1938, Chief of General Staff, BEF (British Expeditionary Force), France, 1939-1940, Commander-in-Chief, British Forces in Northern Ireland, 1940-1941, and Chief of Staff to Supreme Allied Commander, South East Asia Command, 1943-1944, with aerial photograph of Belfast, Aug 1940, and a group photograph of the officers of South East Asia Command [1945], typescript extracts from reports, letters and typescript extract from the diary of Maj Gen Edmund Archibald Osborne, on the campaign in France, 1940. Also, printed order of service in memory of FM John Standish Surtees Prendergast Vereker, 6th Viscount Gort, 10 Apr 1946, and related newspaper cuttings. The diaries were published as Chief of Staff. The diaries of Lieutenant General Sir Henry Pownall, edited by Brian James Bond (Leo Cooper, London, 1972).

The peace divided', an account of his life and career, 1905-1948, notably his service in India with the Queen's Royal Regt, in Africa with King's African Rifles, and in UK, 1938-1940, 1941-1944, Gibraltar, 1940-1941, South East Asia, 1945, East Africa, 1946-1947 and Berlin, 1948, compiled in 1970 by Ben Lockwood, Hart Dyke's stepson, from notes left by Hart Dyke and printed in1995. 'Normandy to Arnhem, a story of the infantry', an account of his service with 4 Bn, (Hallamshire Bn), York and Lancaster Regt in the UK, 1943-1944, and North West Europe, 1944-1945, written using regimental war diaries in 1946 and originally printed in 1966, reprinted by 4 Bn, Yorkshire Volunteers in 1991.

Papers relating to Crick's service in the Western Desert, 1941-1943, as Instructor, War Intelligence Course, School of Military Intelligence, Matlock, Derbyshire, 1943-1944, and with Operational Intelligence, G2 Division, Supreme Headquarters Allied Expeditionary Forces (SHAEF), 1944-1945, including copy of War Diary, General Staff Intelligence Branch, Headquarters 8 Army, 25 Sep-31 Oct 1941; typescript memorandum by Crick 'The possible effect of CROSSBOW on OVERLORD', on how Operation CROSSBOW, (Allied countermeasures against German V-weapons), could influence Operation OVERLORD, (the Allied invasion of occupied Europe), Mar 1944; typescript memorandum by Crick 'The heart of Germany', on the importance of the Ruhr industrial region to Allied strategy, Mar 1944; typescript report by Crick on visit to OKW (Oberkommando der Wehrmacht, the German Armed Forces High Command), Flensburg, Germany, 11 May 1945. Papers relating to Crick's service with the British Joint Services Mission, Washington DC, USA, 1953-1956, including typescript text of lecture by Maj Gen Sir Kenneth William Dobson Strong, Director of Joint Intelligence Bureau, on UK and US Intelligence collaboration and spheres of influence [1953]; typescript memorandum 'Probable Bloc preoccupations in Asia, including Middle East, until mid 1955' [1953]; papers relating to the reorganisation of the Economic and General Division of the Joint Intelligence Bureau, 1956. Papers relating to the Imperial Defence College tour of Pakistan, India, East Pakistan, Ceylon and Aden, Aug-Sep 1960, including itineraries, travel arrangements, three photographs, invitations and a printed map of the Middle East showing oil wells, refineries and pipelines, 1960. Manuscript and typescript notes for a lecture by Crick entitled 'A career in Intelligence', given at Intelligence Corps course, with one audio tape of 20 minute lecture by Crick on interrogation techniques, Ashford College, Kent, Oct 1984. Edition of In the caves of the mind. Poems by Alan Crick (Privately published, Rye, Sussex, 1992). Newspaper cuttings, photographs and publications, 1938-1959, including German newspaper cuttings relating to the visit to Danzig by Rt Hon Alfred Duff Cooper, First Lord of the Admiralty, Aug 1938; three editions of Battledress. The Cadet magazine, Feb-Jun 1940; nine editions of The Crusader Eighth Army Weekly, Oct 1942-Apr 1943; sixteen editions of 'Interim. British Army of the Rhine Intelligence Review', Jun 1945-Apr 1946; three editions of 'Occupation. British Army of the Rhine Intelligence Review', May-Jul 1946. Edition of '21st (British) Army Group in the campaign in North West Europe 1944-1945. Lecture by Field Marshal Sir Bernard L Montgomery to the Royal United Service Institution, London, October 1945'; six photographs and five copies of photographs of Crick, Western Desert and Germany, 1941-1945, and two group photographs, Staff and Students, Joint Services Staff College, 1948, and Military Attachés Conference, Episkopi, Cyprus, 1959.