Carbon pricing is widely considered a key policy instrument for achieving substantial climate change mitigation. However, implementation remains patchy and price levels vary significantly across countries and regions. In this article, we analyze the structural social, political, and economic conditions under which carbon prices have been implemented so far. We estimate a Tobit regression model to investigate variations in explicit carbon prices over 262 national and subnational jurisdictions. Our results highlight well-governed institutions and public attitudes as the most important conditions for carbon pricing and characterize fossil fuel consumption as a barrier to the implementation of carbon prices. The results suggest that governance and public attitude need to be integrated into political economy analysis. Policy makers should take regulatory capacities and public attitudes seriously when designing carbon pricing policies.

As international climate negotiations under the UNFCCC have adopted the goal to limit the increase in global mean temperature to well below 2° C, a highly differentiated—but largely uncoordinated—global climate governance system has emerged. Although coordinated global collective action for mitigating climate change sufficiently to meet the 2°-C goal is still lacking, a multitude of multilateral, minilateral, transnational, national, subnational, and nonstate actors have emerged. This article offers a critical specification of the attempt by Elinor Ostrom and those influenced by her in the literature to conceptualize this climate governance reality as a polycentric approach. We claim that the concept of polycentricity offers high descriptive value for understanding the horizontal and vertical differentiations of current climate governance, and present systematic analysis of a polycentric approach to deliberately enhance the design of the emerging global climate governance architecture. To systematize the Ostromean literature on polycentric climate governance, we identify and specify four key features for climate mitigation governance and their related mechanisms: an emphasis on self-organization , a recognition of site-specific conditions , the facilitation of experimentation and learning , and the building of trust . After discussing objections to a polycentric approach, we conclude by tentatively evaluating its potential to enhance the effectiveness of climate mitigation, and identify central tasks for the efficient design of a polycentric global climate governance regime.