The study of innovation places primary emphasis on studying technological change. In particular, radical innovations have been defined as innovations embodying new technologies that create new markets or disrupt existing ones (Dahlin and Behrens, 2005;Garcia and Calantone, 2003). Most of these studies on radical innovation are based on the Schumpeterian idea that radical technological change can undermine the competitive advantage of incumbent firms by rendering their established technology, and their underlying competencies, irrelevant (Schumpeter, 1934;Tushman and Anderson, 1986). However, innovations also come with institutional change, which is especially the case for radical innovations that usually do not resonate with existing regulations, norms and values (Freeman and Perez, 1988).Since the 1980's, a growing body of literature has paid attention to the effects of institutions on innovation. With the elaboration of the notion of technological regimes (or paradigms) came a conceptual shift from studying technological change to studying the co-evolution of institutional and technological factors (Constant, 1987;Dosi, 1982;Geels, 2002;Nelson and Winter, 1982;Rip and Kemp, 1998). Technological regimes or paradigms are cognitive structures that relate to "technicians' beliefs about what is feasible or at least worth attempting" (Nelson and Winter, 1982, pp. 258-259). This positions an emerging technology in an institutional environment that is determined by dominant evaluation schemata based on accepted technologies. These paradigms and regimes are treated as selection environments, which determines what technologies are successful and become widespread (Dosi, 1982;Van den Belt and Rip, 1987). As such, Garud and Rappa (1994) have argued that for technology to progress, researchers' individual beliefs about technology and the form and function of technological artefacts should resonate with the institutionalized evaluation routines that shape the direction of technological progress at the macro-level.While early studies focused on how beliefs of firms and technicians shape the technological regimes, Kaplan and Tripsas ( 2008) developed a life-cycle model of technological change that focuses on the beliefs and frames of a wider array of actors. They argue that the technological frames -i.e. lenses through which different actors define and interpret a technology -of producers, users and institutional actors interact in shaping the development of collective frames around the meaning of new technologies. While this shifts the exclusive attention away from the producer-side of innovation by taking into account more actors, most studies still depart from the notion of innovation as essentially technological change. Indeed, scholars of radical innovation have concentrated on products or the production process and as such radical innovation tends to be equated This thesis takes a more structural approach to studying the legitimization processes of what I will call 'institutional innovations'. Hargrave and Van de Ven (20...