[3] She belonged to an experienced political dynasty: her father, Welsh-born Morgan Phillips, was a former coalminer who served as General Secretary of the Labour Party between 1944 and 1962; her mother, Norah Phillips was a former member of London County Council who became a life peer in 1964 (allowing Dunwoody to be styled "The Honourable"), serving as a government whip in the House of Lords, and as Lord Lieutenant of Greater London from 1978 to 1986.

Like her husband, she also served as a junior minister, as a Parliamentary secretary at the Board of Trade, and also lost her seat at the 1970 general election.

[3] In 1969 whilst serving as Parliamentary secretary to the board of trade she presented rock band Led Zeppelin with gold discs in recognition of the group exporting £5 million of records to the USA (£111,000,000 in 2024) From 1970 to 1975, she was Director of the Film Producers Association of Great Britain and Consultant to the Association of Independent Cinemas.

[5] She returned to the House of Commons after the February 1974 general election, becoming MP for the safe Labour seat of Crewe, having received the sponsorship of the National Union of Railwaymen[6] (later part of RMT).

In 1983, Dunwoody stood for election as Deputy Leader of the Labour Party, alongside Peter Shore, on a Eurosceptic platform[3] (a position she consistently maintained throughout her career - she voted against the Maastricht Treaty seven times[3]).

[citation needed] She did not return to ministerial office, but served as a front bench spokesman on, by turns, transport, health,[7] and foreign affairs during the 18 years of Labour opposition from 1979 to 1997.

In this role she was a credible, independent-minded critic of the government, and she and her committee discomfited witnesses from the rail and air transport industries.

[citation needed] An attempt by the government whips to remove her and Donald Anderson, Chair of the Foreign Affairs Select Committee, from their positions after the 2001 general election led to a revolt by back-bench members of Parliament, which resulted in them both being reinstated.

[3][4] The Daily Telegraph described her as "Clever, acerbic, fiercely independent and often just plain funny", noting her willingness to cast party allegiance aside.

[15] In late September 2007, Dunwoody beat Irene Ward's record of the longest total service for a woman MP, at 37 years, 9 months.

In early December 2007, she beat Barbara Castle's record of the longest unbroken service for a woman MP, at 33 years, 9 months.