"Many state and local governments are facing significant fiscal challenges, forcing policymakers to confront difficult trade-offs as they consider how to allocate scarce resources across numerous worthy initiatives. To achieve their policy priorities, it will become increasingly important for policymakers to concentrate resources on programs that can clearly demonstrate that they improve their constituents' quality of life. To identify such programs, cost/benefit analysis can be a powerful tool for objectively adjudicating the merits of particular programs. On the surface, all such programs aim to improve quality of life, but whether they actually achieve -- or will achieve -- what they aim for is another question. Summarizing the existing high-quality academic research on the cost of crime and the effectiveness of police in preventing crime, this paper familiarizes policymakers and practitioners with current research on these issues and demonstrates how this research can be used to better understand the returns to investments in police. It demonstrates a method for comparing the costs of police personnel with the expected benefits generated by those police in terms of reduced crime. Applying the method to several real-world scenarios shows that these investments generate net social benefits. Returns on investments in police personnel are likely to be substantial."--Provided by publisher.