1 Introduction It is no longer possible, if it ever was, to ignore noncitizenship. Liberal democratic analyses till now have largely been citizenist. That is, they have focused on citizens, or people insofar as they relate to States as citizens. Efforts to address problems of global justice, including with regard to migration, have mostly focused on expand ing citizenship’s scope. This fails to account for the reality of another sort of special relationship, that of ‘noncitizenship’. This book argues for the recognition of noncitizenship as an analytical category as fundamental to the liberal State as cit izenship. The two are not mutually exclusive, and individuals may well relate with a particular State both as citizens and as noncitizens. When noncitizenship is not dormant, but ‘activated’, this book presents how there arises a specific State obligation not to impair, and sometimes to facilitate, individuals’ capabilities. This includes their dynamic capabilities to affect their own circumstances and the conditions for justice. The form of this obligation depends upon context. From afar, this may relate primarily to obligations to refrain from internal and foreign policies with deleterious effects far away. A State’s activities should not impair the capabilities of those who relate to it as noncitizens, including from a distance. When noncitizens are in transit, noncitizenism challenges strong restrictions on movement and the impediments to capability to which these give rise. Sometimes it may even require actively facilitating a person to move. Within a State, it relates directly to the production of conditions which enable noncitizens to flourish. These various instantiations of noncitizenship are not distinct, but rather flow into each other. Crucial to understanding the implications of noncitizenism is the role of noncitizens themselves in helping to construct their world, through what will be defined in this book as ‘dynamic capabilities’. The purpose in this book is to examine noncitizenism and the obligations to which activated noncitizenship gives rise. This will require both the introduction of new terms and the re-examination of existing ones, which will be picked up and explored throughout the book. Introducing noncitizens People relate to a State as noncitizens for different reasons and to different extents, from those who have never visited the State in question, to those who