The article discusses how the European Union and its member states comply with the Kyoto Protocol on climate change. It looks at how the EU's expansion affected its obligations under international law. The researchers explore how the EU and new member states use flexible mechanisms to meet their Kyoto Protocol targets. They also analyze whether the EU follows the rules of the international climate regime. The study concludes by discussing the principle of loyal cooperation within the EU and how it relates to Kyoto Protocol obligations.