This book defends the idea of autonomy as the balancing of normative arguments, which captures the essential feature of autonomous judgement as being simultaneously free and normatively bound. However, this approach runs counter to the dominant view of arguments as propositions, and to Kantian notions of autonomy. Here, it is applied to three core dimensions of law: law as legal system, as legal practice, and as normative judgement, leading to specific views of legal validity, legal interpretation, and the necessary content of law in the form of human rights principles. Lastly, the autonomous reasoning perspective is applied to conflicts of law with morality and with competing legal systems.