As the National Health Service (NHS) celebrates its 50th birthday, the new Labour government has proposed a radical shake-up in the way it is organised. The most innovative feature is the creation of localised Primary Care Groups (PCGs) with commissioning and providing functions. Although undoubtedly new, there have been earlier initiatives in the NHS which give insights into the problems PCGs will encounter. This article draws upon evidence from these initiatives and places it in a framework for analysis based upon the concept of localisation. It argues that PCGs are more likely to succeed if they are rooted in an evidence-based approach to policy and management.