Organization Intelligence Corps

University of Cambridge

Downing College, Cambridge

North Thames Gas Board (1948-1957)

British Broadcasting Corporation (consultant and contributor | The Great War | 1964 | The Lost Peace | 1965-1966 | The Commanders | 1972-1973)

Churchill College, Cambridge (part-time keeper of the archives | 1977-1995)

Cambridge University (lecturer in defence studies | three years in the 1980s)

Council of the Royal United Services Institute for Defence Studies

Eastern Arts Association

East Anglian Writers Association

Haganah

Israeli Defense Forces

United Nations (Israeli ambassador)

Israel (President)

Roman Catholic Church

All Souls College, Oxford University (Fellow)

Royal Artillery

Institute of Race Relations

Cambridge Apostles

Royal West Kent Regiment

King's College, Cambridge

Bletchley Park (Hut 3)

Friends' Ambulance Unit

Welsh Guards

King's Royal Rifle Corps

Malvern College

Charterhouse School

Special Operations Executive

Royal Artillery

Laurentian University

United Nations

International Labour Organization

GCHQ

Nuffield College, Oxford

Oxford Intelligence Group

Bletchley Park

Conservative Party

Royal Sussex Regiment

Foreign Office

League of Nations

Order of St. John of Jerusalem

English Speaking Union

Martins Bank

Radio Free Europe (broadcaster)

British Broadcasting Corporation (Czechoslovak Service, 1970s-1981)

Charter 77 (translator from Czech to English)

North Cyprus Herbarium (founder)

Royal Engineers

Zionist Organization

Eighth Army