Van Baalen, a jurist and management consultant by occupation, worked for Deloitte as Director of Public relations from his graduation in 1988 until 1999. He became a Member of the House of Representatives on 28 September 1999 serving until 23 May 2002. After the Dutch general election of 2003 he was re-elected as Member of the House of Representatives serving from 30 January 2003 until 14 July 2009 when he became Member of the European Parliament. Van Baalen served as President of the Liberal International from 20 April 2009 until 26 April 2014.