Owen was previously a British civil servant in a career spanning more than 20 years. He worked in H M Treasury, the office of the Prime Minister, and the UK Department for International Development. He has been the private secretary to the Prime Minister and to two Chancellors of the Exchequer. He also took breaks from the civil service to work in the South African Treasury, the Center for Global Development and to be a Visiting Scholar at the University of California at Berkeley. He has been on the board of several NGOs. Owen was also the Director of aidinfo – a programme of Development Initiatives which aims to make aid more transparent and accountable.