This chapter examines the rise of radical right-wing nationalist parties and radical anti-globalization, anti-austerity left-wing parties in Europe. Anti-establishment parties are not new; they have always been a feature of European politics. The ground was not seeded for their development and expansion, however, until social and cultural changes that began in the 1960s combined with the economic and migration crises of the 2000s. The chapter discusses historic anti-establishment parties and the new parties that have emerged over the last two decades. It discusses the nature of anti-establishment parties and describes contemporary radical-left and extreme-right parties. The label of ‘populism’ as applied to these parties is analysed. Using a comparative approach, the chapter examines why there has been a growth of support for anti-establishment parties and attitudes in the last decades, focusing on the development of a ‘populist moment’ in contemporary representative democracies.