This article presents an analytical framework for systematically studying the relationships portrayed within music-based peacebuilding and their respective representations of peace. Music activities with peacebuilding objectives work predominantly within a relational concept of peace, bringing into existence relationships between sounds, people, and spaces through which behaviours such as non-dominance and cooperation can be enacted. However, each of these relationships can communicate different ideas about peace and its manifestation, communications that may be inconsistent with each other and with the activity’s peaceful intentions. The “harmonious relations” framework that this article introduces is a tool for capturing and analysing these embedded relationships and representations. It uses concepts of harmony as a heuristic for critically appraising music’s potential contributions to peace in development contexts, synthesising ideas about relationships in peace and music from peace studies, musicology, philosophy and anthropology. The case of the Zohra Ensemble from Afghanistan illustrates its application.