Stephen studied Biochemistry at the Universities of Edinburgh and London. He worked on energy policy in the 1980s, including the privatisation of the electricity and gas industries, and served in the British Embassy in Washington. He was Director of Communications for the Department of Trade and Industry in the 1990s. From 2000 to 2019 he held senior positions representing the financial services industry. He is a Freeman of the City of London, and Trustee of a number of local and national charities, including the Knapp Foundation. He is a Fellow, and Honorary Secretary, of the Knapp Foundation.