The rule of law is the most important political ideal today, yet there is much confusion about what it means and how it works. This book explores the history, politics, and theory surrounding the rule of law ideal, beginning with classical Greek and Roman ideas, elaborating on medieval contributions to the rule of law, and articulating the role played by the rule of law in liberal theory and liberal political systems. The author outlines the concerns of Western conservatives about the decline of the rule of law and suggests reasons why the radical Left have promoted this decline. Two basic theoretical streams of the rule of law are then presented, with an examination of the strengths and weaknesses of each. The book examines the rule of law on a global level, and concludes by answering the question of whether the rule of law is a universal human good.