Social innovation concerns the development of new products, methods, and services for and with society involving not only citizens, but also public authorities, business and industry, and academia—i.e., the four constituencies of the “Quadruple Helix”—in their design, development, and execution. Social innovation engages and empowers citizens, enhances the resilience of communities, increases the relevance, acceptance and uptake of innovation, and helps foster lasting changes in social practices, therefore acting as a system changer. It thus helps answering societal and environmental challenges, connecting society with innovation.