Much literature on the public policy process focusses narrowly on the policy-making part. This unit widens the focus to examine the implementation phase, and how change happens as a result of new policies: that is, policy – action relationship. It does this by looking at four different models of how this relationship can work through examples from varying fields. The unit will be of interest to public sector managers, their staff and the general reader. This study unit is just one of many that can be found on LearningSpace, part of OpenLearn, a collection of open educational resources from The Open University. Published in ePub 2.0.1 format, some feature such as audio, video and linked PDF are not supported by all ePub readers.