Isabelle Saint-Saëns is an activist in the fields of migration, feminism, and collectivity. She is a member of the transnational network migreurop.org, which addresses European policies of migration and advocates freedom of movement; of Gisti, a French NGO providing information and support to migrants; and of the collective editorial board of Vacarme, a journal that reflects on the intersections of artistic practice, research, and political activism. She participated in the European network Frassanito and was the coordinator of the website Pajol.eu.org, which is now an archive of the Sans Papiers movement (1997–2007).