Populism is considered one of the most contested concepts in the social sciences, notoriously difficult to define. The association of populism with the radical right has further muddied the waters. Particularly in the popular media, populism is conflated with demagoguery, political manipulation, the provision of simple solutions to complex problems, and the promotion of a black-and-white view of politics and the world in general. As a result, populism has acquired a thoroughly negative connotation. However, the association between the radical right and populism is often taken as a foregone conclusion rather than critically probed and interrogated. This chapter discusses the nature of populism, its core narratives, and mechanisms; explores to what extent the radical right can be said to have adopted populism and what explains the radical right’s populist turn; and analyzes the impact of the populist turn on the radical right, its ideology, and its electoral appeal.