Book excerpt: As contemporary policing becomes ever more complex, so knowledge of practical psychology becomes ever more important in everyday policing encounters, situations and contexts. This book suggests how new ways of applying psychological knowledge and research can be of benefit in a range of policing contexts, for example, beat patrols, preventing crime and using the self-selection policing approach to uncover serious criminality from less serious offences. Looking forward, Jason Roach suggests how psychological knowledge, research and policing might evolve together, to meet the changing challenges faced by contemporary policing. In encouraging critical thinking and practical application, this book is essential reading for both police practitioners and criminology, policing and psychology students.