This chapter offers conceptual and practical tools to understand and combat the rise of post-truth politics in the 21st century. It establishes an argument about the extent to which the United Kingdom's (UK’s) Brexit referendum that has been shaped and is continuing to be shaped by post-truth politics. The UK’s referendum on the European Union (EU) membership, now infamously known as Brexit, took place on 23 June 2016 in the UK and Gibraltar. The purpose of the vote was to gauge support for the country either remaining a member of, or leaving, the EU. By referring to Brexit as an ‘ideal-type’ case study for understanding the mechanisms and the effects of post-truth politics, the chapter shows how the Vote Leave campaign around the referendum was built on misleading narratives that touched very sensitive topics such as the National Health Service and immigration control.