No model of the innovative process has been more frequently attacked and demolished than the so-called “linear model of innovation” (Figure 1). At one time it was almost impossible to read a book or an article on technology policy or technological forecasting that did not begin or end with such a polemic. The notion that innovation begins with a discovery in “basic science,” proceeds with an application or invention derived from this fundamental work (“applied science”), and ends with the development of a new product or process (an “innovation”) was indeed at one time quite influential.
However, this linear model was never in fact so strongly upheld as the intensity of the polemical critique might suggest. It is actually quite difficult to find a clear statement of the linear theory from someone who firmly believed in it. Perhaps the best source is in the document that advocated setting up the National Science Foundation in the United States after the second world war. In his proposal, entitled “Science, the Endless Frontier,” Vannevar Bush  did indeed outline a linear model of science, technology, and innovation, and this report was certainly influential among policy-makers both in the United States and elsewhere. The linear model cannot therefore be dismissed simply as a convenient straw man erected for the convenience of those expounding alternative ideas.
Freeman, C. 1996. The Greening of Technology and Models of Innovation. Technological Forecasting and Social Change, Vo. 53, pp.27-39.