The nuclear controversy is rapidly growing in Europe at a time when sizable nuclear projects are being undertaken. The development of that controversy did not occur simultaneously in the different European countries, but the evolution of its successive steps happened to be remarkably uniform and quite similar to what has been occurring in the U.S. The opposition to nuclear energy evolved along with some collective phenomena, such as the greater preoccupation toward environment, that began primarily in the U.S. Although administrative systems are considerably different in centralized and in federal countries, everywhere people are demanding more information and a greater participation in decision-making processes. Controversy is being strengthened by this trend toward “direct democracy”; this was particularly perceptible in centralized countries such as France, but was also apparent in such federal countries as Germany and Switzerland, where the opposition began much earlier. Proper information cannot be easily dispensed in such an overheated atmosphere. The role of mass media has been and will be very important, but the media usually prefer broadcasting the alarming rather than the reassuring news. The credibility of information sources is a major point. State-owned utilities (in Britain or France) draw some benefit from their financial independence, although they are considered as responsible for decisions on nuclear projects. Atomic energy commissions and ministerial licensing or controlling bodies remain independent from the industrial companies. Scientific associations are not greatly developed in Europe although the situation is beginning to change. Presently, it seems essential to rely on such intermediate bodies as physicians, politicians, and university professors to inform the man in the street.