From the job loss in the secondary sector in France since 1970, there is evidence that this sector still plays a discriminant part in the national economy, on the one hand, and that de-industrialisation results in a two-sided interplay, on the other hand : the spreading out of industrial phenomenon, notably originating from Paris and the Ile-de-France Region, still causes many rural «communes» to industrialise in turn ; tertiarization is greatly an outcome of this industrial diffusion : enhancing of the social services, development of business services, detached from their secondary clients, that concentrate on their own competitive advantage in a globalizing market. This advantage may frequently be gained from R&D, leading to new products and processes. Related to the presently deregulating sector of telecommunications, the French telephone industry is an example of these dynamics of a multinational firm facing opportunities and constraints, and of territorial actors acting for industrial development.