About one-fifth of the U.S. population between the ages of 18 and 64 lacks health insurance and the size of this group is expected to rise as the cost of health care premiums increases. Using data on 37,089 adults at 60 sites from the 2000-2001 Community Tracking Household Survey (CTHS), the authors of this study look at the relationship between an individual's reported access to care and community uninsurance levels. Surprisingly, the main results show that the community uninsurance rate has a relatively large and consistent impact on health care access for the insured subpopulation—but not for the uninsured subpopulation. The authors estimate that a five percentage point increase in the community-level uninsured population is associated with a 10.5 percent increment in the likelihood that an insured adult will report having unmet medical needs within the last 12 months. This result does not change when the number of physicians per capita and the average month hours of charity care provided by local physicians are included in the analysis. The main findings of this study are policy relevant because insured adults are typically in a better economic position to influence the political process. As awareness grows of the negative consequences of community uninsurance for the insured, the likelihood of adopting reforms aimed at increasing health insurance coverage will become greater.