This special issue of the International Journal of the Sociology of Agriculture and Food, which has been co-edited by Yuna Chiffoleau and Allison-Marie Loconto, presents the results of recent and innovative research on social innovation in the global agro-food sector. Social Innovation in Agriculture and Food: Old Wine in New Bottles? By: Yuna Chiffoleau, Allison Marie Loconto Transformative Social Innovation for Food Sovereignty: The Disruptive Alternative. By: Paula Juárez, Florencia Trentini, Lucas Becerra The Emergence, dynamics and agency of social innovation in seed exchange networks. By: Bálint Balázs, Guntra Aistara London’s urban agriculture. By: Les Levidow Factors for Effectiveness of Social Innovations in Urban Agriculture. By: Dona Pickard Solidarity Purchasing Groups in Italy. By: Lara Maestripieri, Toa Giroletti, Antonello Podda Urban Food Movements and Their Transformative Capacities. By: Cordula Kropp The transformative potential of social innovation. The case of wheat and bread value chain in Tuscany. By: Adanella Rossi, Riccardo Bocci