This book explores the emergence of ecological sustainability as a new EU policy and legal objective, distinct and autonomous from sustainable development. It argues that sustainability can no longer be conflated into sustainable development only, but should rather be represented as a plural construction, in which ecological sustainability coexists next to sustainable development. While the latter orientates most of the regulatory measures stemming from the Green Deal, the former is playing an increasingly relevant role in a number of legislative initiatives. The volume considers whether and how the EU legislator is exploiting the new opportunities brought forth by the redefinition of sustainability. To do so, a thematic approach is adopted and the inquiry is organized in five different parts, each devoted to one specific transition triggered by the European Green Deal. Navigating the dynamics of the many transitions occurring in the horizon of European climate neutrality, key chapters shed light on the EU regulatory schemes through which ecological sustainability is in the process of being operationalized and critically discuss their points of strength, weaknesses and underlying tensions. In doing so, they provide an overview of the legal changes occurring in areas of topical interest such as agri-food, energy, digitalization, corporate governance and intellectual property, as well as a number of insights on the relevance of ecological sustainability for the internal dynamism of the European Green Deal. This extensive and innovative appraisal of the field will prove a stimulating read for academics, researchers and advanced students interested in the new ecological law stemming from the Green Deal, the changing features of sustainability and the relevance of the Green Deal as a regulatory project.