Susanna Justine McGibbon (born 11 November 1967) is a barrister and senior British civil servant who currently serves as HM Procurator General, Treasury Solicitor and Head of the Government Legal Service, and so Permanent Secretary of the Government Legal Department.

[3] McGibbon worked as a private practice barrister after being called to the bar at Lincoln's Inn in 1990.

[3] Following a brief spell in private practice, McGibbon joined the Government Legal Profession first at the Foreign and Commonwealth Office before moving to the Treasury Solicitor's Department (GLD) in 1998 (where she also worked in the Ministry of Defence for two years).

[1][2][3] On 18 February 2021, it was announced that the Cabinet Secretary had, with the approval of the Prime Minister, appointed McGibbon to be the new Treasury Solicitor[2] following the resignation of Sir Jonathan Jones.

[3] She lists her recreations as travel (particularly Europe and Asia), music and "generally enjoying London life".