The material at Churchill Archives Centre begins with Lord Gladwyn's school and college notebooks, and runs to his final articles, but with the exception of his personal and family correspondence, was chiefly created after Lord Gladwyn's retirement from the Diplomatic Service. A large proportion of the papers consists of notes, reports, articles, speeches and correspondence amassed from Lord Gladwyn's work as the Deputy Leader of the Liberal Party in the House of Lords and Liberal spokesman on foreign affairs and defence (1965 - 1988), his place on Parliamentary Delegations to the Council of Europe and WEU Assemblies (1966 - 1973), and particularly his work as a Member of the European Parliament and Vice-President of the European Parliament Political Committee (1973 - 1976). The collection also includes photographs, press cuttings and other material from his time as British Ambassador to France.

There is also a large amount of literary material, including research notes, interviews, and drafts of Lord Gladwyn's works, chiefly on European affairs and defence and also a series of diaries and notebooks from 1929 - 1995.

The papers also include the memoirs of Irene Hunter, Lord Gladwyn's secretary, under Gladwyn Associated. Although these memoirs cover Mrs Hunter's whole career, they do include reminiscences of her work for Lord Gladwyn while he was British Representative to the United Nations and British Ambassador in Paris, and also after his retirement from 1968 onwards.