Ken is the Conservative Member of Parliament for Rushcliffe and the Shadow Secretary of State for Business, Enterprise and Regulatory Reform.

He was in permanent ministerial employment throughout the 18 years of successive Conservative governments, from 1979 to 1997, serving in the Cabinets of both Margaret Thatcher and successively John Major. Since the Conservative defeat of the 1997 general election he had been a backbencher until his return to frontline politics in the Shadow Cabinet as Shadow Business Secretary in 2009. He has contested the Conservative Party leadership three times—in 1997, 2001 and 2005—being defeated at all attempts. Though considered popular with the general public, his defeats were attributed to his famously pro-European integration views which conflict with the Conservative Party's scepticism of the EU, demonstrated by his being President of the Conservative Group for Europe. Despite this, Conservative leader David Cameron appointed Clarke to the shadow cabinet in January 2009.