ng the EU greenhouse gas emissions trading scheme (EU ETS) was delivered hardly five years after adoption of the EU ETS Directive.1 The amendment of the EU ETS agreed upon politically in December 2008 strives 88 Exploring Uncertainties in the EU ETS CCLR 1|2009 * Marjan Peeters is Professor of Environmental Policy and Law, in particular climate change issues, at Maastricht University. Stefan Weishaar is Assistant Professor at Maastricht University. This paper was written in the contract-research framework “Emissions Trading and Equal Competitio