Greville has been Chairman of Trustees of Waterloo Uncovered from the formation of the Charity in 2016. He enjoyed a full career in the Army, initially with the Grenadier Guards and latterly the Coldstream Guards. He experienced operational service in Northern Ireland, Iraq and Afghanistan and peacetime service in Germany and throughout the UK which included ceremonial duties in London. He is passionate about providing opportunities that support the recovery of serving military personnel and veterans adversely affected by their military service.