Social ecologists argue that individual change and environmental manipulation must work together for the prevention initiative to be effective. Thus, preventive education may lead individuals to change drinking behavior if the surrounding alcohol environment is reconfigured to support change and if occupants of the environment understand how they are expected to change. A general approach to prevention planning is proposed that has three phases: assessment and validation by local citizens that a problem exists in the community environment; commitment to courses of action to change the local environment; and institutionalization of sustained efforts to maintain gains that have been achieved. Two projects are detailed that demonstrate the community planning process, the San Francisco Prevention Project and the Castro Valley Prevention Planning Project. The San Francisco project did not move to self-sustaining activities to modify problematic alcohol environments, but the Castro Valley project did. Factors relevant to the different outcomes are support from key community leaders, work across several agencies and groups, media coverage, multiple program activities, program backup and additional support as needed, and differences in project startup. 18 references