Sustainability as a reference frame for dealing with the interconnection of environmental, economic and social issues on a global scale is not only characterized by complex problems and long-term strategies but also by differences and disagreements with regard to its meanings and how they should be realised. Therefore, Rather than seeking a single most appropriate definition of Sustainability, the main focus of this book is on how specific Sustainability problems are defined by whom and in which contexts, what solutions are pursued to tackle them, and which effects they have in practice. This account of the social nature of Sustainability is intended to assist its readers to better understand the complexities, dynamism, and ambivalence of this concept as well as to find their own position in relation to it. For this purpose, the book traces the historical development of the larger discourse on Sustainability and investigates responses to three grand Sustainability challenges: climate change, energy, and agricultural food production. It suggests that promoting Sustainability requires continuous and active care and is inseparable from political debate about the normative foundations of society.