Morgan McSweeney is an Irish and British political strategist. He has served as Downing Street Chief of Staff under Prime Minister Keir Starmer since October 2024. McSweeney was the campaign manager for the Labour Party and director of the think tank Labour Together.
McSweeney built a reputation as a Labour organiser, leading successful campaigns to win a majority on the Lambeth London Borough Council and to defeat the far-right British National Party in Barking and Dagenham. In 2017, he formed Labour Together during the Labour Party leadership of Jeremy Corbyn, where he sought to replace Corbyn and to reduce left-wing influence in the party. In 2020, he led Starmer's successful Labour leadership campaign and subsequently Labour's successful campaign in the 2024 general election.
In June 2024, The New Statesman ranked McSweeney first on a list of the most influential shaping progressive politics in the UK, having described him as Starmer's "most trusted aide". In October 2023, The Times stated that "nobody without elected office wields as much power in British politics as McSweeney".
