Frank Ernest Field, Baron Field of Birkenhead, CH, PC, DL (16 July 1942 – 23 April 2024) was a British politician who was the Member of Parliament (MP) for Birkenhead for 40 years, from 1979 to 2019, serving as a Labour MP until August 2018 and thereafter as an Independent. In 2019, he formed the Birkenhead Social Justice Party and stood unsuccessfully as its sole candidate in the 2019 election. After leaving the House of Commons he was awarded a life peerage in 2020 and sat in the House of Lords as a crossbencher.

From 1997 to 1998, Field served as the Minister of Welfare Reform in Tony Blair's government. Field resigned following differences with the Prime Minister; as a backbencher he soon became one of the Labour government's most vocal critics.

Field was elected Chair of the Work and Pensions Select Committee in June 2015. Following the 2017 general election he was re-elected unopposed.

In August 2018, Field resigned the Labour whip citing antisemitism in the party, as well as a "culture of intolerance, nastiness and intimidation" in parts of the party, including in his own constituency.[2] Field lost a confidence vote in his constituency party a month before his resignation, after siding with the government in Brexit votes. His resignation of the whip also led to his departure from the wider membership of the Labour Party, according to the Labour National Executive Committee, although Field disputed this.[3]