The work presented here is structured in three parts. The first provides the theoretical framework from which the general problem analysed is addressed: the representation of the difference in the context of inter-ethnic relations. The second highlights the importance of studying this problem for the development of intercultural education and, more specifically, for a better understanding of how one of its key players, teachers, makes this difference. The third provides an interpretation of the partial results of an empirical investigation. It is concluded that, at least in this case, the perception of the ethnic difference is linked to the construction of the identity itself and to hierarchical categorisation processes, which are explained by the ability of the dominant group to classify and place the others on a perceived cultural distance scale.