This book examines key themes, debates and issues in contemporary public law. It identifies and draws out five key themes: the notions of government and the state; the place of the state and public law in the world at large; relationships between institutions and officials within the state; the legitimacy of institutions; and the identity and value of public law in relation to politics. The book also presents a contemporary examination, taking account of the substantial changes witnessed in this area in recent decades and of the resulting need to reassess orthodox accounts of the subject. Written by leading authorities drawn from across the common law world, their approach is rigorous, engaging and highly accessible. This Companion acts as both a thoughtful introduction and a collection that consciously moves the discipline forward.