Mowery and Rosenberg (1979) temporarily put to rest a rather vigorous debate that had been raging since Schumpeter’s work (1934) on the relative importance of market demand versus technological opportunity as incentives for innovation. Schumpeter (1934) argued forcefully that entrepreneurs are driven by technological opportunity but was rebuffed by Schmookler (1962) who showed that increases in demand preceded increases in inventive activity over the business cycle. Research in the 1960’s and 1970s tended to side with Schmookler, possibly most prominently with the research by Chris Freeman et al. (summarized in Freeman, 1982) where they conclude that market (or user) “need ” is the most important driver of innovation. Other studies claimed to find similar strong dominance of market pull/need over