Since approximately 10 years, research in medieval art history has aknowledged both the importance and the great range of the mobility of artists, works of art and models during the Middle Ages. However the questions raised by such circulations are not only that of the identification of those circulations. By using the notion of artistic transfers, the analysis presented here wants to understand artists', works of art's and models' circulations in their dynamic relation with both their origin and host cultural environment. The term and the notion of "artistic transfers" implies indeed a displacement of persons, objects or terms from a cultural space to another. It is relevant for art history as it allows to adress the problem in other terms than those of artistic influence or reception. It is therefore very useful to take into account the disruptive dimension of such circulations and the "political and cultural conjuntures" (M. Espagne and M. Werner) such transfers suppose in the relation between different cultural areas. Such an approach also allows to raise a variety of questions that have rarely been dealt with regarding the social availability of artists, homogeneity of technical or cultural practices and the permeability of knowhows. What is the signification of those artist's presence so far away from their original areas ? Which were the reasons and "political conjuntures" explaining those circulations ? Furthermore, which were the constraints outsider artists were submited to ? Did those contraints have any influence on their production and its elaboration ? What was the place assigned to this production in their host system ? In return, have the system they came from been reconfigured by those transfers ? All those questions, and many more, can be answered by an analysis in terms of artistic transfers. The mechanisms at stake should be pictured in a larger frame than that of art history only, as they are dependent on the very cultural possibilities of such exchanges.