In the past 25 years, the application of public health approaches to violence has yielded a new perspective, one that views violence as preventable. This public health paradigm has revealed not only important risk and protective factors that could serve as intervention points but also a deeper understanding of the nature of violent behavior. Violence has a tendency to cluster, spread from setting to setting, and transform from one type to another. Rather than occurring at random, violent events tend to follow other violent events. Whether the events are geographically close or distant, there seem to be mechanisms that contribute to a contagion of violence.