My paper will focus on the relationship between France and Romania in the field of informatics in a particular period, the Détente. I will lean upon various sources, depending on the archives of a French firm, the CII (Compagnie Internationale pour l’Informatique), and of French public administrations: the ministries of Foreign Affairs, of Finances, of Defense and of the Industry. I will demonstrate that the Franco-Romanian cooperation was both supported and circumscribed by the Cold War. Indeed, it was Romania’s peculiar stand in between the Soviet bloc, allegedly autonomous, which allowed France to develop this cooperation in a high technology field. Without the peculiar time of Détente, which favored the building of scientific, technical and industrial links between Eastern and Western countries, this would not have been possible either. Finally, these considerations were combined with the French desire to resist United States’ hegemony in informatics. If Franco-Romanian ties were exclusive at the beginning, the French industry – backed by the French government – had in fact to compete more and more with the American industry and government. On the contrary, both France and the United States stood cautious of teaching the most up-to-date discoveries of their own Research & Development to the Romanian engineers they had to train and, sometimes, to receive in their own country. Actually, the Soviet-Romanian cooperation in the field of technology intelligence kept being felt a menace for the West. Though, it was paradoxically when this worry proved the most pregnant that the cooperation was set up.