Risk Terrain Modeling (RTM) is an approach to risk assessment in which separate map layers representing the spatial influence and intensity of a crime risk factor is created in a geographic information system (GIS). Then all map layers are combined to produce a composite risk terrain map with values that account for all risk factors at every place throughout the landscape. RTM builds upon principles of hotspot mapping, environmental criminology, and problem-oriented policing to produce maps that show where conditions are ideal or conducive for crimes to occur given the environmental contexts. RTM is a statistically valid way to articulate and communicate crime-prone areas at the micro-level according to the spatial influence of criminogenic features. The “Risk Terrain Modeling Manual” (2010) presented the theoretical framework and complete steps of RTM. The “Risk Terrain Modeling Compendium” presents applications and concepts of RTM that were not already discussed at length in the RTM Manual. Part 1 presents an overview of risk terrain modeling, explains the history of its development, and discusses techniques for operationalizing spatial influence. Part 2 is a series of literature reviews with risk factors that are known to be related to a variety of crime types. Part 3 demonstrates how RTM may be applied to different crime types and settings, and how it can be used for a variety of practical endeavors, such as forecasting crime or evaluating place-based interventions. Part 4 concludes the book with thought pieces about RTM's potential applications to research, technologies, and activities related to public safety and security.