Tensions between police and diverse communities in both the US and UK require innovation about ways to improve relations. While police diversity is often discussed as a potential solution, these discussions lack theoretical and empirical support. This volume presents an original discussion of race, gender, sexual orientation and class diversity and shows that police diversity can have meaningful impacts on the decision-making, outcomes and legitimacy of police forces. Drawing on theoretical and empirical research including interviews with diverse police leaders, this book examines how police diversity can help shift traditional policing cultures. It also considers obstacles to police reform, revealing how championing meaningful diversity can positively impact the lives of policed communities.