the theme of this fourth volume is Voice in traditional music. Singing or spoken, it is the key communication body. In many civilisations, it is also the supreme reference for instrumental music, whose criteria of excellence are based precisely on its ability to imitate the voice, reproduce the patch and inflexions. The concept of musical aesthetics is highly cultural, and the existence of countless vocal techniques relativises the western conception of the purity of the voice. Such diversity is now leading to more and more research, both semantic, anthropological and musicological. The contributions to this document provide a broad overview.