Mark Stephen Fullbrook (born June 1962)[1] is a British political strategist and lobbyist who was Downing Street Chief of Staff from September to October 2022.
He established and briefly was CEO of his own consultancy firm, Fullbrook Strategies Limited, between May and September 2022, which advised Liz Truss during her ultimately successful Conservative Party leadership campaign.
[3] In his role, Fullbrook had advised former speaker of the United States House of Representatives Newt Gingrich, as well as David Trimble and Boris Johnson between June and July 2019 for his successful Conservative Party leadership campaign.
[4] He has been interviewed by FBI agents about an alleged criminal plot to bribe the former governor of Puerto Rico, Wanda Vázquez Garced, on behalf of Julio Herrera Velutini, a Venezuelan banker.
[3] The Cabinet Office informed the public that Fullbrook's service for the Prime Minister would be paid through his lobbying company in a highly unusual arrangement that could allow him to pay less tax.