Frédéric Sawicki is a professor of political science at the Université Paris I – Panthéon-Sorbonne. He studies political parties and the sociology of activism. A specialist on the French Socialist Party, he has published Les Réseaux du parti socialiste: Sociologie d’un milieu partisan (1997, with Rémi Lefebvre), La Société des socialistes: Le PS aujourd’hui (2006), and “Political Parties: Socialists and the Left,” in Development in French Politics 5, ed. Alistair Cole and Vincent Tiberg (2013). He can be reached at: frederic.sawicki@univ-paris1.fr.