Universal Credit became a policy of government thanks to the surprise appointment of Iain Duncan Smith as Secretary of State for Work and Pensions in May 2010. Though its origins can be seen in a commissioned policy review for the Conservative Party, the policy was largely developed through Duncan Smith’s think tank, the Centre for Social Justice. The development of Universal Credit provides useful insights into the unusual course the policy generation can take and the role of think tanks, as well as highlighting important issues about the difficulties in policy design and implementation planning when it comes to major reform.