Efforts to prevent alcohol and drug problems at the community level have been predominantly oriented toward individuals. Since the 1970's, however, there has been growing interest in more system-oriented approaches that encourage community responsibility for drinking problems, mobilize local efforts in shaping an appropriate prevention environment, and focus on environmental issues and structures instead of only on those persons who drink to excess. Because communities are dynamic, complex, and counterintuitive and involve feedback, bringing a community into the center of prevention has implications for planning, decentralization, respecialization, reintegration, and reorientation of goals and strategies. The complexity and dynamics of a community make it difficult to design and implement "quick fix" prevention programs. Instead, effective changes in community systems take time to produce long-term reductions in alcohol and other drug problems. Prevention involves taking risks and making choices about key targets of intervention, methods and strategies to be used, and balancing different components to enhance overall impact. 32 references