A rapidly growing empirical literature from across the social sciences relates social capital to a diverse array of indicators of well-being, including economic growth (Knack & Keefer, 1997), labor force participation (Aguilera, 2002), violent crime (Galea, Karpati, & Kennedy, 2002), political corruption (La Porta et al., 1997), and even self-reported happiness (Bjornskov, 2003). Of all the phenomena thought to be affected by social capital, health and health-related outcomes have received the greatest attention, evidenced in part by the contributions in this volume. Yet, despite repeated findings of a statistical association between social capital and various health outcomes and risk factors, as well as the existence of plausible causal pathways linking social capital to individual health,3 many health economists are skeptical of the importance of social capital for health (e.g., Mellor & Milyo, 2005).