Sir Mark Sedwill was Cabinet Secretary from April 2018 to September 2020 and National Security Advisor from April 2017 to September 2020. Prior to this, Mark was the Permanent Secretary at the Home Office (2013-17), FCO Political Director (2012-13), NATO Senior Civilian Representative in Afghanistan (2010-11), HM Ambassador to Afghanistan (2009-10) and Director of UKvisas (2006-8). He joined the Foreign & Commonwealth Office in 1989, serving in Egypt, Iraq, Cyprus and Pakistan.

Mark was educated at the University of St Andrews and the University of Oxford. He is a Fellow of the Royal Geographical Society, a Fellow of the Institute of Directors and President of the Special Forces Club.