In 2014, HM Treasury launched the Financial Management Reform programme (FMR): today it is widely seen as one of the most successful and mature of the UK civil service's reforms. The purpose of this joint paper by the Institute for Government and the Chartered Institute of Management Accountants (CIMA) is to allow those interested in improving finance functions in other complex organisations (especially centres of government) to see what is happening in the UK, and to understand the way this change has been undertaken. Similarly, this paper is an opportunity for those involved in other UK reforms to understand recent developments in Whitehall’s finance function.