The study of far-right parties and politics is one of the most high-profile research areas in political science and related disciplines. Far-right parties have been the subject of vast amounts of varied scholarship since their turn-of-the-century resurgence. However, as the far right has become a mainstay, with Brexit and the election of Donald Trump in 2016 blurring the boundaries between mainstream and far-right politics, it has become crucial to pay attention to the process of mainstreaming. Beyond a focus on far-right electoral success, studies of mainstreaming, as well as a critical account of the concept and role of the ‘mainstream’, have proved elusive. This article provides a heuristic framework to understand these concepts and the mainstreaming of the far right. Key to our approach is a more holistic analysis, extending beyond traditional approaches which focus mostly on the electoral outcomes of far-right parties, positioning the mainstream as a relatively inert target or bulwark against them. To achieve this, we seek to reframe the focus towards the centrality of discourse both in the process, and as an outcome, of mainstreaming. Only by doing so can we account for the significant role played by the mainstream in this process.