[en] In assessments of the dependability of the western world's uranium supply between now and the year 2000, and also of the conditions under which the next century will have to be faced, the following questions may be raised: (1) Are the resources in the ground sufficient. Are the reserves equal to those of other mineral substances. In the light of present estimates of speculative resources, when will it become necessary to develop the breeder system. The study concludes that exploration will have to be intensified and preparations made now for the commercial introduction of breeders as from the beginning of the next century; (2) Is the mining industry able to meet the increasing demand. Despite the reductions in nuclear power programmes which have helped mask the difficulties of the mining industry, the growth in demand continues to be rapid; however, it should be possible to cope with this if the uncertainties of the market do not discourage investors in the mining industry; (3) Will the mining industry have to face the possibility of a sudden surge in demand. The possibility of an abrupt reduction in supply or a sudden increase in demand cannot be ruled out. A crisis scenario based on assumptions which the authors consider to be realistic would result in a 300,000 t increase in demand within 15 years; (4) Can uranium circulate freely between the producer and the consumer. This is the most disquieting problem, in view of the unequal distribution of resources between the world's consumer countries and producer countries (not including the United States of America) and of the embargo risks threatening international trade on such a strategic product. The average level of dependence of consumer countries (except the United States) for uranium supplies is around 80 per cent; this situation is likely to induce the less privileged countries to develop processes - such as the breeder system - which conserve uranium and thus reduce their dependence. (author)