Although a pesticide industry had been present in France since the end of the nineteenth century, the use of pesticides only became dominant in French agriculture after World War II. The marginalization of other methods of pest control at the turn of the 1950s cannot simply be explained by policies in favor of agricultural intensification. This chapter provides an account of the important work carried out by the French pesticide industry to transform crop protection. This industry sought to impose itself as the most exclusive resource possible in the areas not only of pesticide regulation but also of crop protection research and practices. Based on two of the instruments that the pesticide industry set up at the time, a professional journal and a learned society, this chapter describes how it built a corporate systemic ascendency on different actors of the French crop protection. It shows that this ascendency relied on four long-term dynamics: the organization of the pesticide industry into a formidable business association, the pathologization and medicalization of crops, the professionalization and increased technicity of crop protection, and establishing of an ideological hold over actors of crop protection.