The first paper argues that police action does make a difference in public safety; structured, proactive, tightly focused response can reduce the incidence of a wide range of offenses, but careful evaluation is essential to document what interventions are effective. The second paper provides practical guidance for police personnel or others who are responsible for evaluating police tactical patrol. The first two sections provide general information on tactical patrol and on evaluation methods. The next four sections describe four evaluation designs, illustrate their use in evaluating tactical patrol, and then provide step-by-step instructions. A paper on community-policing evaluation first defines community policing and then discusses the operational context for its evaluation, operationalizing programs within the community policing framework, the political dimension, and the practical aspects of performance evaluations for community policing. The paper on proactive investigations evaluation discusses issues of definition and research design, in tandem with available and accessible information relevant to evaluation. The concluding paper addresses evaluation design of differential police response, which is intended to maintain an optimum balance between too much and too little police resource allocation in responding to requests for police service. Chapter references