Commodification and transnational trading of ecosystem services is the most ambitious iteration yet of the strategy of ‘selling nature to save it’. The World Bank and UN agencies contend that global carbon markets can slow climate change while generating resources for development. Consonant with ‘inclusionary’ versions of neoliberal development policy, advocates assert that international payment for ecosystem services (PES) projects, financed by carbon-offset sales and biodiversity banking, can benefit the poor. However, the World Bank also warns that a focus on poverty reduction can undermine efficiency in conservation spending. The experience of ten years of PES illustrates how, in practice, market-efficiency criteria clash directly with poverty-reduction priorities. Nevertheless, the premises of market-based PES are being extrapolated as a model for global REDD programmes financed by carbon-offset trading. This article argues that the contradiction between development and conservation observed in PES is inevitable in projects framed by the asocial logic of neoclassical economics. Application in international conservation policy of the market model, in which profit incentives depend upon differential opportunity costs, will entail a net upward redistribution of wealth from poorer to wealthier classes and from rural regions to distant centres of capital accumulation, mainly in the global North.