Sir Gavin Alexander Williamson CBE (born 25 June 1976) is a British politician who served in various Cabinet positions under Prime Ministers Theresa May, Boris Johnson and Rishi Sunak between 2016 and 2022, lastly as Minister of State without Portfolio from 25 October to 8 November 2022 under Sunak. A member of the Conservative Party, he has been the Member of Parliament (MP) for Stone, Great Wyrley and Penkridge, formerly South Staffordshire, since 2010. Williamson previously served as Government Chief Whip from 2016 to 2017 and Secretary of State for Defence from 2017 to 2019 under May, and as Secretary of State for Education from 2019 to 2021 under Johnson.

Williamson was born in Scarborough, North Yorkshire, and was educated at Raincliffe School, Scarborough Sixth Form College and the University of Bradford. He was chair of a Conservative student body from 1997 to 1998. He served on the North Yorkshire County Council from 2001 to 2005. In the 2005 general election, he stood to become MP for Blackpool North and Fleetwood, without success. Williamson was elected as MP for South Staffordshire at the 2010 general election. He served in David Cameron's governments as Parliamentary Private Secretary to the Secretary of State for Transport, aiding Patrick McLoughlin, prior to being appointed Parliamentary Private Secretary to the Prime Minister in October 2013.

Following Cameron's resignation, Williamson supported Theresa May's bid to become Conservative leader; May appointed Williamson as Chief Whip in her first government in July 2016. He later served as Secretary of State for Defence from November 2017 to May 2019, when he was dismissed following a leak from the National Security Council; Williamson denied leaking the information about Huawei's potential involvement in the British 5G network. After supporting Boris Johnson's campaign to succeed May as Conservative leader, Williamson returned to the cabinet as Secretary of State for Education in July 2019. He served in the role during the early part of the COVID-19 pandemic, including times when schools were closed to most children, and was criticised for the 2020 school exam grading controversy. In September 2021, he was dismissed as Education Secretary when Johnson reshuffled his cabinet. He was subsequently nominated by Johnson for a knighthood, which he obtained in March 2022.

Williamson supported Rishi Sunak in his two attempts to become Conservative leader; following Sunak's election in October 2022, he appointed Williamson as Minister of State without Portfolio. In November 2022 Williamson resigned, stating he wanted to clear his name "of any wrongdoing" in relation to allegations, which he "strenuously denied", of him having bullied former Chief Whip Wendy Morton and of bullying behaviour previously during his own tenure as Chief Whip and as Defence Secretary.

Williamson was born in Scarborough, North Yorkshire. His father Ray was a local government worker, and his mother Beverly worked in a job centre. They were both Labour Party voters. He attended East Ayton Primary School and for his secondary education, Raincliffe School, a comprehensive. He studied A-Levels in History, Economics, and Government and Politics at Scarborough Sixth Form College. From 1994 to 1997, he completed a BSc in Social Sciences from the University of Bradford.

Williamson was national chair of Conservative Students in 1997, the penultimate chair before it was merged into Conservative Future in 1998. As chair he accused the National Union of Students (NUS) of acting like a "branch of the Labour Party". In 2001, he was elected as the Conservative county councillor for Seamer division in North Yorkshire. In 2003, he was appointed as the County Council's "Young People's Champion". He did not stand for re-election in 2005. Williamson is a former deputy chairman of Staffordshire Area Conservatives, chairman of Stoke-on-Trent Conservative Association and vice-chairman of Derbyshire Dales Conservative Association.

Williamson worked as a manager in fireplace manufacturer Elgin & Hall, a subsidiary of AGA, until 2004. Williamson had become managing director of Aynsley China, a Staffordshire-based pottery firm by 2005. It sold ceramic tableware and he later became co-owner. In April 2005, Williamson was quoted in reports on the consumer rush to buy items with the wrong wedding date on for Charles and Camilla's wedding. He told The Daily Telegraph, "We've literally had fights in our own retail shops. On the first day after the announcement I went into our factory shop in Stoke-on-Trent and we had people fighting over the last plate that we had on the shop floor. I think everybody has decided that this is going to be their pension."

He has also worked for NPS North West Limited, an architectural design firm, until he became an MP in 2010.