This Pocket Guide fills a critical gap in the literature by providing state-of-the-art techniques for researchers, graduate students, and agency administrators. Research in criminal justice settings represents unique challenges that require rigorous designs and a suite of methods, as well as the tools to navigate a complex system. With this accessible and practical guide, readers will encounter a wide range of study types and data sources, along with strengths and weaknesses to consider with each as they conceptualize, implement, and analyze their research. Crucially, the authors also provide advice on how to gain and manage access to these settings, as well as templates for preparing a successful Institutional Review Board application. Step-by-step procedures elucidate the use of extant and administrative data, and practical case examples, sample forms, and measures will help researchers implement their studies quickly and effectively.