The social-ecological model emerged from ecological systems theory (Bronfenbrenner, 1979), which explicitly sought to examine transactions between persons and their environments. The model stresses cross-level influences, in which community or organizational environments can shape individual behavior (top-down effects), but also examines how individuals form groups or take actions that may affect higher level organizational or community spheres (bottom-up effects). The Centers for Disease Control and Prevention has incorporated social-ecological models into a number of its health promotion and disease prevention efforts. The simple onion or Russian doll rendering of social-ecological relations as concentric circles is not in itself very informative. However, flowchart models based on such relationships can be useful for specifying hypothesized cross-level influences. Read more