The EU Emissions Trading System (EU ETS) is important through its role as the “cornerstone” of EU climate change policy as well as a “role model” and “pioneer” for carbon markets. It is important that, in addition to the regulatory requirements, it be subjected to a thorough and independent review, to discover if it delivers on explicit, and what have become “expected” objectives, as well as discover any issues that need to be better understood. Availability of public data has been identified as a barrier to some parts of this analysis. The State of the EU ETS Report aims to be an independent contribution to the policy debate, which is needed to ensure that the EU ETS is “fit for purpose.” This report discusses the current state of play in the EU ETS while abstaining, to the extent possible, from providing solutions.