This book critically analyses different dimensions in the sustainable transitions outlined by the European Green Deal, focusing on both internal actions and external relations and highlighting the EU’s diverging powers and capabilities in achieving the core objectives. As with the Green Deal itself, the chapters cover different policies including financial instruments, energy policies, climate policies and external policies and apply the ideal-type logics of appropriateness and consequences to analyse sustainable transformations. The variety of the cases contribute to a broad understanding of how different actors interpret and implement the aims of the European Green Deal, including especially those lagging behind, who, for various reasons, are struggling with the sustainable transition. From examining their policies, the book illuminates the challenges and opportunities they are facing. Overall, the contributions address key questions surrounding the EU’s powers and limits in inducing transformative change and implementing the European Green Deal. This book will be of key interest to scholars, students and practitioners of EU sustainability policies, sustainability transitions and green economy, environmental studies, energy policy, energy governance and climate change, public policy, comparative politics and international relations.