The Ecole de Chaillot, training department of the Cité de l'Architecture et du Patrimoine, has extensive experience in the training of architects who wish to specialize in heritage. The School has developed cooperation with universities and training institutes in other countries wishing to benefit from this experience by welcoming teachers from the Ecole de Chaillot in their own training. Thus, a close cooperation was established in 2000 with Bulgaria. The Cité de l'Architecture et du Patrimoine has the Erasmus Charter since 2009, and developed ever since its partnership with the University of Architecture, Civil Engineer and Geodesy in Sofia to establish teaching mobilities to train architects who wish to specialize in the field of heritage, training organized in partnership with the National Institute of cultural monuments of Sofia. The Ecole de Chaillot does not offer student mobility to students following its Diplôme de spécialisation et d’approfondissement mention Architecture et patrimoine, as this post-master training is followed by students in parallel with their professional practice, they are therefore unavailable for mobility during their curriculum. Under the Erasmus+ 2014 project, 17 teaching mobilities took place between October 2014 and November 2015. They are 8 teachers that the Ecole de Chaillot has sent in Bulgaria, each of them for between 1 and 5 teaching mobilities. Most of them had already carried out teaching mobilities under previous Erasmus projects, including with the Bulgarian partner that they know well. There are especially confirmed teachers, architects, historians and archaeologists, with technical knowledge that is requested and appreciated by the Bulgarian partner. These mobilities represent 260 hours of teaching, both lectures and practical sessions, particularly in the context of the study of a heritage site. Indeed, after several days on site, students work on this subject for a year during tutorial sessions. In Sofia there are 31 Bulgarian students taking this course now, it is the 7th session since the creation of this course in 2000. Student work made during the Tcherepichki workshop (May 2015 - June 2016) will be presented to the Cité de l’architecture et du patrimoine in early 2017: this is an opportunity to disseminate the results of these teaching mobilities among teachers and students of the Ecole de Chaillot, but also to a wider audience. Such exposure had already taken place in Paris in February 2014 with the exhibition of the work done during the Skortsité workshop in the year before. This cooperation is beneficial for teachers who perform these teaching mobilities : indeed they point out that this mobility allows them especially to acquire useful skills for their professional practice, to expand their professional network, and to put in practice new teaching practices. These good results encourage the Ecole de Chaillot to continue its cooperation with its Bulgarian partner and pursue teaching mobilities.