The foreign languages and cultures teaching is in full development and in profound questioning for about fifty years, in particular concerning the preparation of the new generations to the globalization. Having recalled the various aspects of this development, we analyze the mission which I given from now on to the professors as intercultural mediators. But can we teach, and how, the cultures and the interculturality which ask for an apprenticeship different from that of the language? The professor has to be able to create a dialogue between the cultures in contact, between the resemblances and the differences which he envisages with his learners without sinking into moral judgment or into absolute relativism. The question of the universality must be openly approached without taboo because depend on it the pluri-, multi-, inter- or trans-cultural societies which we announce, projects which we should not confuse but to which we contribute sometimes unconsciously. Having pleaded in favour of the analyse of the cultural profile of the learners and having warned of the risks of not taking it into account, we insist on the crucial importance to cultivate the diversity not only in the contents of the courses, but also in their objectives, in their methodologies and especially in the way of conceiving the learner and the learning. The challenge for the professors of foreign languages and cultures to come is to educate to/in the diversity by avoiding the confusion, to/in the universality by avoiding the standardization.