The chapter explores the growth, scope, and impact of the academic literature that has arisen since the publication of Open Innovation back in 2003. Moreover, the chapter further clarifies and develop the conceptualization of open innovation, which it defines as a distributed innovation process based on purposively managed knowledge flows across organizational boundaries, using pecuniary and non-pecuniary mechanisms in line with the organization’s business model. On this basis, the chapter then discusses divergent views on open innovation and it calls for greater consistency in future research. Next, the chapter addresses some of the critiques on the notion and development of open innovation as they have emerged in the literature so far. Finally, the chapter considers the progress open innovation research has made, relative to the research agenda identified in Chesbrough, Vanhaverbeke, and West (2006), and extend the possible research subjects and units of analysis.