 As comptroller and auditor general, Bourn certified the accounts of all UK Government departments and a wide range of other public sector bodies; and he had statutory authority to report to Parliament on the economy, efficiency and effectiveness with which departments and other bodies used their resources.Under his leadership, the National Audit Office won contracts to carry out substantial work overseas, including for the United Nations, the European Commission, and for a number of countries around the world.During his tenure Bourn was Chairman of the Multilateral Audit Advisory Group of the World Bank, and he also was a member (and chairman) of the Panel of External Auditors of the United Nations.