The turn to market-based instruments, such as emissions trading, in environmental policy has received considerable attention. Contributing to a critical assessment of these instruments by investigating the political theory of emissions trading, one of their central mechanisms, namely their depoliticising effect, is highlighted by discussing the early contributions of neoliberal thinkers and proponents of market-based instruments (Hayek, Coase, Dales) in environmental governance. These thinkers responded to the growing politicisation of environmental limits to economic growth by devising a mechanism by which the implementation of these limits could be depoliticised. This ensured that the fundamental questions of "what is produced, by whom, and for whom" (Hayek) are not raised politically. Emissions-trading mechanisms are neoliberal, not in the sense that they commodify or privatise nature, but because they entrench the power of investors.