Contributor(s): Professor J. McKenzie Alexander, Dr Ilka Gleibs, Professor Alan Manning | Across the world, populist agendas on both the left and right threaten to undermine fundamental principles that underpin liberal democracies, so that what were previously seen as virtues of the ‘Open Society’ are now, by many people, seen as vices, dangers, or threats. As global citizens, we are implicated by a range of contemporary social questions informed by the Open Society; from the free movement of people to the erosion of privacy, no-platforming and the increased political and social polarisation fuelled by social media. Expanding on Karl Popper’s thinking nearly 80 years since the original publication of his spirited philosophical defence of the Open Society, J. McKenzie Alexander’s new book, The Open Society As An Enemy, argues that a new defence is urgently needed now, in the decades since the end of the Cold War. The Open Society as an Enemy interrogates four interconnected aspects of the Open Society: cosmopolitanism, transparency, the free exchange of ideas, and communitarianism. In re-examining their consequences, Alexander calls for resistance to the forces of reaction, alongside his claim for the concept of the Open Society to be rehabilitated and advanced.