This paper focuses upon the increasing propensity of the EU to engage in climate change unilateralism. EU climate unilateralism consists of two key components. First, it extends the reach of EU climate change law beyond the borders of the EU and regulates GHG-generating activities that may be viewed as taking place abroad. Second, this geographical extension in the scope or reach of EU climate change law is contingent in the sense that the EU may agree to waive the external application of its climate change law if adequate climate change regulation has been put in place internationally or by other states. EU climate unilateralism is most apparent in the recent revisions to the EU’s emissions trading scheme (ETS)