The economic crisis, the fall of the Berlusconi government and the birth of the technocratic government led by Mario Monti have produced several changes in the Italian political system. Certainly, one of the most important innovations in the context of Italian politics has been the emergence of the Five Star Movement. Such a new party has achieved spectacular overnight success in several elections at sub-national level, and now it is the most voted party in the 2013 national elections. The Five Star Movement combines antiestablishment rhetoric with demands for political reform. The article analyses the electoral growth of the Five Star Movement using both aggregate data and individual data from “Osservatorio Politico CISE” (i.e. cross-section and panel surveys conducted from November 2011 to March 2013). In particular, the author investigates whether the profile of the supporters of the Five Star Movement has changed over time, both from a political and a social standpoint. Finally, the author analyses what factors influence the electoral choice for the Five Star Movement, also from a longitudinal perspective.