Professor Matthew Kramer is one of the most important legal philosophers of our time - even if the label 'legal philosopher' does not do justice to the breadth of his work. This collection of essays brings together esteemed philosophers, as well as junior scholars, to critically assess Kramer's philosophy. The contributions focus on Kramer's work on legal philosophy, metaethics, normative ethics, and political philosophy. The volume is divided into six parts, each focusing on different aspect of Kramer's work. The first part, Rights and Right-holding, contains five essays addressing Kramer's work on rights and right-holding, including the Hohfeldian analysis and the interest theory of right-holding. The four essays in the second part, General Jurisprudence, focus on Kramer's work in general jurisprudence, from the compatibility of legal positivism with universal legal error, to his robust defense of inclusive legal positivism, concluding with reflections on his writings on the rule of law. The third part, General Matters of Ethics, contains two essays addressing Kramer's metaethical work on moral realism as a moral doctrine. The fourth and fifth parts, Freedom and Liberalism, have four essays falling within political philosophy, probing Kramer's work on negative freedom and political liberalism, respectively. The sixth part, Applied Ethics, contains two essays on Kramer's work on capital punishment and freedom of expression. The collection is rounded off by reflections on, and replies to, the contributions by Kramer himself.