This article contributes to the literature on environmental governance in industrialized democracies by showing that effectively conserving biodiversity requires different institutional strategies than reducing air emissions. Institutional effectiveness diminishes as the politically contentiousness of the issue increases, moving from biodiversity to air pollution, and then climate change. Drawing on Lijphart's theory of consensus democracy and theories of functional and actorcentered federalism, we use the 2010 Environmental Performance Index and panel analysis on twenty-one OECD countries to show that consensus-based party systems improve performance. We find that centralization generates greater improvements with respect to air pollution than biodiversity, but that decentralized strategies can improve biodiversity when implemented alongside corporatist bargaining structures.