The Institute of Legal and Constitutional Research’s annual Academic Lecture was delivered by Professor Don Herzog of the University of Michigan Law School on 28 September 2017. Professor Herzog’s title was ‘Sovereignty, RIP: Part of the Story’. He proposed that arguments concerning sovereignty continue to be dominated by ideas that were developed in the early modern period. Such ideas, with their emphasis on the undivided, unlimited, and indivisible nature of sovereignty, may have been well-suited to that period but are now not merely outdated but also pernicious and malign in their effect. Even in earlier contexts such as eighteenth-century conflicts over American independence and the U.S. Constitution, debates framed by both sides in terms of sovereignty were often rendered harder to solve by use of the concept and in particular emphasis on indivisibility. Often, argued Professor Herzog, abandonment of ideas of sovereignty and their replacement by ones such as ‘jurisdiction’ would have a beneficial effect.