Using the state as the unit of analysis, this study gauges the effects of various state policy interventions on rates of uninsurance, private coverage, and Medicaid coverage for the nonelderly population. The study controls for economic structures, population demographics, and characteristics of the health-service market. Then, using Wisconsin counties as units of analysis within a common regulatory environment, the relative importance of economic and demographic characteristics of the health-service market are tested to see if any of these factors can explain overall rates of health insurance coverage.