Mark Fullbrook is the Founder and CEO of Fullbrook Strategies Limited, a consultancy specializing in crisis management, grassroots organizing, and research-driven campaigns. He is recognized as a political strategist and campaigner, having advised figures such as Boris Johnson, Liz Truss, Newt Gingrich, and David Trimble. Fullbrook served as Chief of Staff to Prime Minister Liz Truss at 10 Downing Street from September to October 2022.