Evidence based medicine has had a major impact on clinical practice. There is an urgent need for the Public Health community to further develop its own evidence base as many interventions are introduced, unchallenged with no hope of evaluation as the tools for this do not exist. This well structured text aims to provide the tools to achieve this aim. Mindful of the varying needs of students, practitioners and policy makers, the author highlights key take home messages for each and provides practical methods, and their theoretical basis, for applying evidence to the field of Public Health. Some of the methods are well established, others are newly developed by the author and colleagues. The book is aimed at all health students and practitioners, at whatever level, with the hope that the reader will apply these methods to their thinking, research and practice.