Objective. To examine the relationship between social capital and preventable hospitalizations (PHs). Data Sources. Administrative and secondary data for Florida (hospital discharge, U.S. Census, voting, nonprofits, faith-based congregations, uninsured, safety net and primary care providers, and hospital beds). Study Design. Cross-sectional, zip code-level multivariate analyses to examine the associations among social capital, primary care resources, and adult PHs and pediatric asthma hospitalizations. Data Extraction. Data were merged at the zip code-level (n 5 837). Principal Findings. Few of the social capital measures were independently associated with PHs: longer mean commute times (reduced bonding social capital) were related to higher adult rates; more racial and ethnic diversity (increased bridging social capital) was related to lower nonelderly adult rates but higher pediatric rates; more faith-based organizations (linking social capital) were associated with higher nonelderly adult rates. Having a safety net clinic within 20 miles was associated with lower adult rates, while general internists were associated with higher rates. More pediatricians per capita were related to higher pediatric rates. Conclusions. The importance of social capital for health care access is unclear. Some bonding and bridging ties were related to PHs, but differentially across age groups; more work is needed to operationalize linking ties.Key Words. Social capital, access to care, primary care, race and ethnicity, social environment Community-level factors have been associated with access to health care, above and beyond covariates such as individual health status, insurance coverage, and sociodemographics. For example, previous research has found that neighborhood is related to whether individuals report a usual source of care, physician use, receiving preventive care, and having unmet need for care (Kirby and Kaneda 2005;Litaker, Koroukian, and Love 2005). Social capital r Health Research and Educational Trust