This introduction presents an overview of the key concepts discussed in the subsequent chapters of this book. The book aims to develop a particular theory of freedom, and explores the relationships between the view of freedom and issues of social justice. It examines the relationship between freedom and social justice both in theory and practice, and the way in which that relationship has been specified in liberal theories. The book outlines the approach taken to political philosophy and considers the impure theory of freedom and its connections with the idea of social justice. It investigates the three types of condition for freedom: the Non-interference Condition, the Autonomy Condition, and the Power Condition; and focuses on the Autonomy Condition. The programme of social justice called for by the impure theory of freedom, and the characterization of the free agent as an equally active chooser, doer and participator in their community, has a particular shape.