Julian Lewis is the Chairman of the House of Commons Defence Select Committee. He was elected to this post by his fellow MPs in June 2015, shortly after being elected as the Conservative MP for New Forest East, in Hampshire, for the fifth time since 1997. In September 2010, the Prime Minister appointed him to the Intelligence and Security Committee for five years and, in October 2014, he was additionally elected as a member of the Defence Select Committee. From November 2002 until May 2010, he was the Shadow Defence Minister for the Royal Navy, the nuclear deterrent and strategic issues. He held this post continuously, except for a period as Shadow Minister for the Cabinet Office between September 2004 and the May 2005 General Election.

Julian was appointed to the Privy Council in March 2015.

Currently a Visiting Senior Research Fellow of the Centre for Defence Studies, in the Department of War Studies, King's College, London, Julian read Philosophy and Politics at Oxford before specialising in Strategic Studies. He was awarded his doctorate in 1981 and a book based on his research, Changing Direction: British Military Planning for Post-war Strategic Defence 1942–47, was published in 1988. A second edition, based on newly-declassified archives, was published by Frank Cass in 2003, and as a University paperback by Routledge in 2008.