The aim of the multidisciplinary research project Corsica Sud-Archives [CO S-A] is to establish a collaboration between PRISM research team (Perception, Representation, Image, Sound, Music Laboratory; CNRS), the Aix-en-Provence Sound Archives (Phonotèque) and the Repertorium Archives held in the Centre National de Création Musicale (CNCM Voce). During two years, we exchange scientific approaches, skills and technologies in order to connect the musical heritage of Corsica with the other resources of the French South region, to increase the circulation of knowledge, and also to improve the visibility of this musical data for musicians and researchers. Moreover, the challenge is to apply a musicological and anthropological reflection on oral tradition to the current and contemporary practice of these repertoires. This collaboration allows to develop in a dynamic way the cultural and historical bridge between artistic actors and the territorial collectivity of Corsica. Through the development of a sustainable relationship on the sharing of intangible archives, the team of [CO S-A] wants to question the methods of preservation and re-use of these archives, while promoting scientific research actions and cultural activities. This paper introduces the process to build this relationship on the field in Balagna (Haute Corse) where the concepts of “legitimacy”, “authenticity” or “cultural borders” are experimented locally.