The RATP, a public service and autonomous enterprise, has always been concerned with "customer satisfaction". A consensus of usage has been created around this term by the RATP and the authorities to which it is responsible: who would not want to satisfy the customers ? This desire to satisfy its customers forms part of a general philosophy of the enterprise where it was both seen and saw itself as a servant of those citizens who were not in a position to use private vehicles on a regular basis. Such customer satisfaction was seen as a particularly vague and not very explicit concept: as such it was not likely to justify the taking of very detailed decisions. Whilst good sense and a strict observing of transport conditions had allowed a simple approach to the efforts to be made by the enterprise, in the sense that the necessary priorities could be clearly seen whilst the assumed dissatisfactions of the users confirmed the difficulties of the enterprise, this concept could be used without posing any major problems. This conceptual vagueness was useful for those inside and outside the enterprise who shared the same vision of things, a vision which we could term administrative.