To survive, let alone flourish, we need to be sure of—securely tied to—at least one other person. We also need to be sure of our general acceptance within the wider social world. This book explores the normative implications of taking our social needs seriously. Chapter 1 sketches out what our core social needs are, and Chapter 2 shows that they ground a fundamental, but largely neglected human right against social deprivation. Chapter 3 then argues that this human right includes a right to sustain the people we care about, and that often, when we are denied the resources to sustain others, we endure social contribution injustice. Chapters 4–6 explore the tension between our needs for social inclusion and our needs for interactional and associational freedom, showing that social inclusion must take priority. While Chapters 5 and 6 defend a narrow account of freedom of association, Chapter 7 shows that the moral ballgame changes once we have made morally messy associative decisions. Sometimes we have rights to remain in associations that we had no right to form. Finally, Chapter 8 exposes the distinct social injustices that we do to people whom we deem to be socially threatening. Overall, the book identifies ways to change our social and political practices, and our personal perspectives, to better honour the fact that we are fundamentally social beings.