Elgar Advanced Introductions are stimulating and thoughtful introductions to major fields in the social sciences and law, expertly written by the world’s leading scholars. Designed to be accessible yet rigorous, they offer concise and lucid surveys of the substantive and policy issues associated with discrete subject areas. In this Advanced Introduction to Social Innovation, Frank Moulaert and Diana Mac Callum present a pioneering exploration of the relatively young field of ‘social innovation’. Delving into the history of innovation, from the 17th century to the present day, the authors investigate the modern preeminence of social innovation in scientific and policy debates, public policy, and collective action in many social spheres. Identifying a range of socio-political and ideological stances, from ‘caring’ liberalism to inclusivity and sustainability, this Advanced Introduction not only provides a compelling reflective survey of social innovation thought and practice, but also offers perspectives on what social innovation is, and what it should be. Concise and perceptive, this timely introduction will serve as an excellent resource for students and scholars of social innovation. Moulaert and Mac Callum’s insight into the explosion of social innovation in the 21st century will also offer practitioners a valuable guide for navigating socially innovative actions and processes.