More than 40 cities have participated in the California Healthy Cities Project since its inception in 1988. Because Healthy Cities efforts are community driven, these cities address diverse health and social issues using a wide variety of strategies. This complexity, in addition to the usual difficulties associated with evaluating community interventions, creates many challenges for evaluation. Given the community building and process orientation of Healthy Cities, it may be most appropriate to measure intermediate community changes that have been linked to health outcomes in previous research or, at a minimum, theoretically. The California Healthy Cities evaluation framework conceptualizes change at five levels: individual, civic participation, organizational, interorganizational, and community. The framework, developed collaboratively with Healthy Cities participants, attempts to synthesize current thinking and practice on evaluation of community projects by applying concepts from community capacity/competence, social ecology, and urban planning.