This third volume of EU Energy Law and Policy Issues presents an overview of some of the most recent developments taking place in the EU energy sector at a time when the Third Energy Package is likely to be, or has been, implemented in the EU Member States. In this respect, the reader will find a number of contributions which offer detailed and critical views on some of the main issues tackled by the Third Energy Package. Aside from this, the relationship between sector-specific regulation and the rules of general competition law is examined in the second section of the book. This section also contains particular contributions on access regimes in gas and electricity markets, as well as an innovating analysis on the methods for allocating allowances under the EU emissions trading scheme and the interaction of such methods with EU State aid rules. Just like the previous volumes of the book, the third section offers a deep insight into the external aspects of EU energy policy. Accordingly, the role of the Lisbon Treaty in promoting EU energy policy in the international arena is scrutinized, in addition to the most recent evolutions on the topical issue of the Energy Charter Treaty. This section is completed with a daring contribution about the need to adopt a comprehensive theory of legal harmonization between the EU and third partners, which is presented using the specific case of the EU-Russia Energy Dialogue. Some fundamental issues regarding the environmental aspects of EU energy policy undergo an in-depth study in the final section of the book. Not only is the legal regime of energy efficiency in energy-related products examined, but also the issue of carbon constraining policies under WTO law. Finally, the electricity industry's viewpoint on the 2020 targets rounds off this third volume with judicious comments.