This is an introduction to constitutional theory, aimed at both scholars and an informed lay audience. The author surveys the theoretical issues raised by judicial practice in the United State since the 1960s, particularly since the Warren Court, and locates both theory and practices that have inspired dispute among jurists and scholars. At the same time, the text also advances an argument about the distinctive nature of American constitutionalism, regarding it as an instance of the interpenetration of law and politics. The work also devotes attention to judicial review and its relationship to American democracy and theories of constitutional interpretation.