IntroductionMounting warnings about the impacts of human activities on the global climate system have led to widespread calls for radical thinking and action to manage the causes and effects of accelerated climate change (Demeritt, 2001). Helm (2003), the prominent climate economist, for instance, wrote that`j ust as the experience of the unemployment of the 1930s required a reinvention of much of macroeconomics, climate change will need new thinking too'' (page 349). Similarly, in the Stern Review: The Economics of Climate Change it was noted that:`C limate change presents a unique challenge for economics: it is the greatest and widest-ranging market failure ever seen. The economic analysis must therefore be global, deal with long time horizons, have the economics of risk and uncertainty at centre stage, and examine the possibility of major, non-marginal change'' (Stern, 2007, page i). Despite this shared conviction about the need for change, virtually every aspect of how actually to respond to climate change remains open to debate. For example, to what extent should policy be pitched towards mitigation or adaptation, and (how) should this change over time? Which technologies should be prioritised for future energy provision, transportation, and industrial activities? How should international trade and security relations be reformed to better align poverty alleviation, food security, and climate protection objectives? How should water, forest, and other natural resources be managed to accommodate future scarcity? And to what extent should strategies be technologically or behaviourally driven?The carbon economy (defined here as any measure that seeks to assign commodity values and create markets for greenhouse-gas emissions) has emerged over the last decade as a major development in the reharnessing of economics for climate protection. For many analysts, emissions trading, carbon taxes, and voluntary carbon offsets have become strategies of first choice because of their claimed ability to deliver economically efficient reductions in greenhouse-gas emissions (Grubb and Ferrario, 2006). Yet, for others the carbon economy's affinities with the``ideological commitments, discursive representations, and institutional practices'' of neoliberalism ( McCarthy and Prudham, 2004, page 276;