Research shows that certain risk factors contribute to the incidence of problem behavior and that specific protective factors buffer the effects of exposure to risk. Risks and protective factors are examined in the context of traditional approaches to crime prevention, such as incarceration, and indirect and human costs of crime. The effectiveness of risk and protective-focused crime prevention is evaluated in terms of the importance of changing community norms, values, and practices and in terms of community policing. Specific risk and protective- focused crime prevention programs are described, particularly with respect to reducing adolescent problem behavior and crime. Implications of the risk and protective-focused paradigm for law enforcement in the 21st century are addressed. 72 endnotes