Cas Mudde is an Associate Professor in the School of Public and International Affairs at the University of Georgia (USA) and a Researcher at the Center for Research on Extremism (C-REX) at the University of Oslo (Norway). He publishes broadly on politics in Europe, Israel, and North America with a particular focus on (the interaction between) extremism and democracy. His main research agenda is informed by the question: How can liberal democracies protect themselves from political challengers without undermining their own core values? His books include "On Extremism and Democracy in Europe" (Routledge, 2016), "Political Extremism" (SAGE, 2014), "Youth and the Extreme Right" (IDEBATE, 2014), "Populism in Europe and the Americas: Corrective or Threat for Democracy?" (Cambridge UP), "Populist Radical Right Parties in Europe" Cambridge UP, 2007), "Racist Extremism in Central and Eastern Europe" (Routledge, 2005), and "The Ideology of the Extreme Right (Manchester UP, 2000). His forthcoming books are "The Populist Radical Right: A Reader" (Routledge, 2016), "SYRIZA; The Failure of the Populist Promise" (Palgrave Macmillan, 2016) and "Populism: A Very Short Introduction" (Oxford UP, 2017).