The collection comprises school papers, 1943-1959, and material relating to his time at Edinburgh University, 1957-1962; files relating to elections, 1961-circa 1990s; political papers, 1954-1981, mainly concerning constituency politics; manuscript diary of the Lib-Lab Pact, 1977-1978; files relating to his involvement in the Scottish Constitutional Convention, 1988-1998, including minutes of meetings and related correspondence; files relating to Scottish politics, 1992-1999, including correspondence, memoranda and reports; files relating to Scottish Parliament Elections, 1997-1999, comprising correspondence, reports, addresses, briefing papers and some related newspaper cuttings; diaries of appointments, 1959-2012, some of these have been closed for Data Protection reasons; letters to and from David Steel concerning his Knighthood, 1989-1990; papers and correspondence relating to his appointment as Lord High Commissioner to the General Assembly of the Church of Scotland, 1998-2003, including correspondence, programmes of events, memoranda and lists of guests with some related ephemera; correspondence files relating to membership of various organisations, 1996-1999; personal and family papers, 1959-1990; personal ephemera and memorabilia, 1953-1997; miscellaneous political ephemera, 1895-1992, relating to the Liberal Party and to other political organisations; audio-recordings, 1979-1987; photographs and slides, 1938-1999, mostly relating to his early years, family connections, national and local politics, meetings with foreign dignitaries, visits abroad and his involvement in the Liberal International; cartoons, 1976-1987; newspaper cuttings, 1960-2006; miscellaneous publications, circa 1930s-1970; objects, circa 1960s-2005.