Traditional approaches to crime prevention may be termed "legal prevention," "social prevention," and "neighborhood/block watch." These approaches rely upon a single rationale to prevent a broad range of crime types. "Legal prevention" relies upon laws and attached punishments to deter all types of criminal behavior. "Social prevention" relies upon the construction or modification of social conditions designed to promote law-abiding behavior in general. "Block Watch" uses general surveillance to detect and deter a variety of crime types in a particular geographic area. In contrast to traditional crime prevention approaches, "situational crime prevention" attempts to prevent a specific crime problem with unique characteristics. Based on an analysis of the crime problem, crime prevention approaches are tailored to the nature of the problem. Examples of situational crime prevention are provided to show how the modification of existing sites or circumstances prevented targeted crime problems. Some examples of planning sites with a view to preventing certain crimes are also provided. 10 notes, 66 references.