Katherine Ruth Gallagher (born 18 March 1970) is an Australian politician who has been serving as the Minister for Finance, Minister for Women, Minister for the Public Service and Vice-President of the Executive Council in the Albanese Government since 2022, and formerly served as the 6th Chief Minister of the Australian Capital Territory from 2011 to 2014. She has been a Senator for the Australian Capital Territory since the 2019 federal election, as a member of the Australian Labor Party (ALP). She previously served in the Senate from 2015 to 2018.