Vulnerability is a large, ambiguous, undetermined, and increasingly relevant concept. It is a notion that engages jurists, philosophers, sociologists and ecologists, all of whom have tried to attribute to it a meaning, a content and a set of characteristics. Vulnerability is also reflected in all or almost all areas of our lives: we experience it in the humanitarian, health, economic and social crises that periodically and mercilessly afflict our societies, exacerbated by the fragility of natural systems and the growing climatic risks. The global climate situation has revealed not only a uniform vulnerability, but also a series of different and variable vulnerabilities that affect human beings, ecosystems, nature, planet, and human and non-human rights. This collective book, prepared by a number of academics from various legal disciplines, questions about the concept and substance of vulnerability, but also addresses its application, its manifestations, and above all its interaction with other concepts and principles already present or currently emerging in the area of Environmental Law. The aim, therefore, is to emphasize this notion as a common denominator of the underlying issues related to climate change in international, European, human rights and biodiversity law.