What is evidence for anyway? It is perhaps worth revisiting some of the early discussions of the initial chapters of this book to reflect on the reasons as to why evidence is seen as important in policymaking in the first place. A number of claims have been made about the benefits of evidence, but perhaps the most common is to hold that more or better uses of evidence can improve decision making in terms of policy effectiveness and programme efficiency (cf. Coalition for Evidence-Based Policy 2015; UK Government 2013). From this conceptualisation, when used accurately and with fidelity to scientific best practices, evidence tells us ‘what works’ to achieve programme goals so as to obtain improved outcomes, to save valuable limited resources and to select effective solutions to social problems (see similar discussion in Dhaliwal and Tulloch 2012; Shaxson 2005). Yet the conceptualisation of policymaking as an exercise in technical problem solving and discussions of evidence which appear to remove political considerations have led to many criticisms of the EBP movement outlined in Chapter 2, including a failure to understand the decidedly contested nature of policymaking and the risk of imposing a de facto set of policy priorities through the promotion of particular types of evidence.