The advent of Internet marked a significant change in how users and customers can be involved in the innovative process. History is rife with examples of how users innovate, but Internet and its associated communication technologies brought radically new means for individuals to interact rapidly and at little cost in communities that spur new innovations. These communities are initiated and governed by people that differ in their motivations for taking part and participate to varying degrees. Such communities are outside the immediate control of companies seeking to develop open innovation strategies aimed at harnessing their work. This book brings together distinguished scholars from different disciplines: economics, organization theory, innovation studies and marketing in order to provide an improved understanding of how technological as well as symbolic value is created and appropriated at the intersection between online communities and firms. Empirical examples are presented from different industries, including software, services and manufacturing. The book offers food for thought for academics and managers to an important phenomenon that challenges many conventional wisdoms for how business can be done. This book was published as a special issue of Industry and Innovation.