Polycentric theory, as applied to sustainability policy adoption, contends that municipalities will act independently to provide public services that protect the environment. Our multilevel regression analysis of survey responses from 1,497 municipalities across the United States challenges that notion. We find that internal drivers of municipal action are insufficient. Lower policy adoption is explained by capacity constraints. More policymaking occurs in states with a multilevel governance framework supportive of local sustainability action. Contrary to Fischel’s homevoter hypothesis, we find large cities and rural areas show higher levels of adoption than suburbs (possibly due to free riding within a metropolitan region).