ABSTRACT. This editorial introduces the special feature on the role of game-changers, broadly conceptualized as macro-trends that change the "rules of the game," in processes of transformative social innovation. First, the key concepts are introduced together with the academic workshop that brought together 25 scholars, from across a wide range of disciplines, to discuss the role of game-changers in transformative social innovation, resulting in the 9 contributions in this special feature. Second, the differing conceptualizations of the role of game-changers in transformative social innovation across the set of articles are discussed. Third, an overview is provided of the different empirical examples of game-changers and transformative social innovations addressed; examples were drawn from different geographical contexts across Europe, North America, South America, Africa, and Asia. Fourth, the differing epistemological approaches used to explain social change are noted, and lessons for interdisciplinary and transdisciplinary research on social change discussed. Finally, a synthesis is provided of the main insights and contributions to the literature.