Political obligation refers to the moral obligation of citizens to obey the law of their state and to the existence, nature, and justification of a special relationship between a government and its constituents. This volume in the Contemporary Anarchist Studies series challenges this relationship, seeking to define and defend the position of critical philosophical anarchism against alternative approaches to the issue of justification of political institutions. The book sets out to demonstrate the value of taking an anarchist approach to the problem of political authority, looking at theories of natural duty, state justification, natural duty of justice, fairness, political institutions, and more. It argues that the anarchist perspective is in fact indispensable to theorists of political obligation and can improve our views of political authority and social relations. This accessible book builds on the works of philosophical anarchists such as John Simmons and Leslie Green, and discusses key theorists, including Rousseau, Rawls, and Horton. This key resource will make an important contribution to anarchist political theory and to anarchist studies more generally.