This book addresses a topic that is currently high on the agenda in many fora: how to specify and secure a social minimum. The term 'social minimum' has different meanings, depending on the context. These contexts are examined in this book from different perspectives, including law, sociology, philosophy, politics and economics. In the first part, the social minimum is discussed from a conceptual and theoretical point of view. The second part shows the various ways in which the social minimum can be specified and measured. There is a need for new indicators that take into account, for instance, aspects of adequate social participation. As this part shows, the choice of indicators is closely intertwined with political choices. The third part approaches the social minimum from the perspective of legal obligations, addressing the nature of different obligations imposed on individuals and states. The fourth part deals with the question of social minimum in the context of courts, adjudication and justiciability. The role of international treaties and national constitutions - the interpretation of the rights they enshrine and the way these are dealt with by expert committees and courts - is discussed with a view to understanding how the guarantee of a social minimum can be promoted within individual countries. Besides being of interest for academics in fields ranging from legal theory and human rights to the social sciences, the book also serves as an important source for students as well as practitioners interested in the social minimum, and anyone who wants to gain an insight into the current debates on this extremely important issue.