[en] Enrichment has been a subject of research and development ever since the beginning of the nuclear industry. Concurrently with the emergence and expansion of the two pioneering technologies, gaseous diffusion and centrifugation, other approaches have been initiated and explored in a number of countries: chemical exchange, the atomic laser, the molecular laser, separation by nozzles, and other aerodynamic processes. Although some were initially promising, most of these approaches had to be abandoned when it was found that they were not industrially viable. It is clear that only three processes still have a future: gaseous diffusion and the atomic laser - the technologies we have chosen to develop - and ultracentrifugation. We accordingly judged it important, in anticipation of the profound changes that will be affecting the energy market in the next two decades, to take stock of this choice and give you an idea of our thinking about the evolution of our production resources. (author)