Health policy is a highly contested arena where there have been increasing calls for policy to be more 'evidence based'. A central question remains 'is evidence-based health policy possible?' This book offers a critical perspective on the interplay between generation and policy formulation. The purpose of this book is to critique the notion that evidence-based medicine can make an unproblematic transformation into evidence approach to health policy that makes use of the best available research in an explicit, rigorous and accountable way. The book is illustrated by eleven case studies of health policy making that elucidate how evidence is used in particular policy making contexts. These case studies provide unique insights from the people who have been involved in the policy process. They reveal the complex nature of evidence-based research. The premise of the book is that although the idea of evidence-based health policy holds considerable promise, it will not be realised without substantial evaluation of the problems, conceptual and practical, that beset it.