We developed a conceptual framework to examine the association between stigma, enrollment barriers (e.g., difficult application), knowledge, state policy, and participation in the Temporary Assistance to Needy Families (TANF) and adult Medicaid programs. Survey data from 901 community health center patients, who were potential and actual participants in these programs, indicated that while images of the Medicaid program and its recipients were generally positive, stigma associated with welfare stereotypes reduced both TANF and Medicaid enrollment. Expectations of poor treatment when applying for Medicaid, enrollment barriers, and misinformation about program rules were also associated with reduced Medicaid enrollment. States that enacted strict welfare reform policies were potentially decreasing TANF participation, while states with more simplified and generous programs were potentially increasing Medicaid participation. The results suggest that the image of the adult Medicaid program remains tied to perceptions about welfare and provides guidance to policymakers about how to improve participation rates. © 2004 by the Association for Public Policy Analysis and Management.