 After leaving Parliament he continued to exercise a rational influence on environmental policy from positions on the executive of the Town and Country Planning Association and the Environment Council's Transport Committee.Following the deaths of Patrick Maitland, 17th Earl of Lauderdale in December 2008 and Bert Hazell in January 2009, Allason became the oldest living former British Member of Parliament.As a sportsman he raced Bentleys at Brooklands, played polo with maharajahs in India, skied and sailed in international competition, and represented the House of Commons in five sports.