552Research on the contribution of neighborhood characteristics to individual health has progressed rapidly over the last decade. Mounting empirical evidence of neighborhood socioeconomic structure (SES) effects on a range of adult outcomes including mortality (Haan, Kaplan, and Camacho 1987), heart disease (LeClere, Rogers, and Peters 1998), number of chronic conditions (Robert 1998), and self-rated health (Malmstrom, Sundquist, and Johansson 1999) has fueled calls for continued research on the health effects of multiple dimensions of community SES and the mechanisms that may account for the community structure-health link (Robert 1999). Despite these efforts, neighborhood effects research on health has typically focused on only one dimension of neighborhood structure-the prevalence of economic deprivation-and has yet to explore competing hypotheses regarding the community level mediators of structural effects on health.We draw on social disorganization and collective efficacy theory (Shaw & McKay 1969;Sampson, Raudenbush, and Earls 1997), Wilson's theory of neighborhood decline (Wilson 1987;, and research exploring the health effects of neighborhood context to elaborate and test two sets of hypotheses. First, we extend the typical focus on the health consequences of neighborhood poverty to include a range of other structural characteristics of neighborhoods including the concentration of affluence, residential stability, and ethnic heterogeneity. Our focus on the role of affluence, in particular, builds on recent theory and research highlighting the potentially important role of middle and upper-middle class residents in anchoring community institutions and providing organizational and economic resources with which to promote a healthy environment (Cagney, Browning, and Wen 2002; Robert 1998). Wilson's theory of social