This chapter tackles the question of local knowledge-making in changing scientific and economic environments in the field of advanced materials. It relies on a case study at the University of Rennes, in Western France, where the chemistry laboratory of Jacques Lucas conducted a program on non-oxide glass materials from the 1960s onwards. The chapter aims at explaining how the local production of these “exotic glasses” in Rennes was both shaped by a bench culture of solid-state chemistry and international R&D supported by the telecommunications industry. This case exhibits how research on materials was organized by a transatlantic division of labor in the Western world.