This paper seeks to advance current understanding of uneven convergence in the context of EU environmental policy, and specifically, the Eco-Management and Audit Scheme (EMAS). Using a large sample, quantitative methodology, we examine three broad sets of determinants hypothesised to influence geographic patterns of policy convergence: (1) cross-national market integration; (2) compatibility between the domestic regulatory context and European policy requirements; and (3) bottom-up pressure from market and societal actors. Our analysis provides empirical support for all three hypothesised determinants. We find that measures of import-export ties, regulatory burden, past policy adoptions, environmental demand from civil society and levels of economic productivity, are all statistically significant predictors of national EMAS counts. Against a backdrop of geographically diverse regulatory institutions, societal conditions and trading relationships, we conclude that unevenness is an inevitable feature of Europeanisation.