Frameworks for the application of the arts in community settings tend to focus on the development of individuals’ empathy or social bonds. A commensurate level of consideration tends not to be given to the socio-economic, political, and institutional forces and processes that shape such development and to how the arts might help build capacities to manage the impact of such forces and processes. The recognition of persons as interdependent in systems reliant on mutual care has implications for applications of the arts in many specialised domains as well as in general public life. Especially in clinical or social interventions, unrecognised institutional dynamics may introduce or maintain imbalances of power in community and professional practice. Music, as a participatory and temporal activity facilitating social synchrony, can foster dialogic and reciprocal relations in social life. To systematise and study a participatory music activity on an organisational and community level, I designed and implemented two collaborative songwriting programs in clinical and social service settings carried out through the nonprofit organisation, Humans in Harmony. One activity, music corps¸ was a two-month program in New York City involving participants from colleges and social service organisations serving adults with disabilities, at-risk youth, and nursing home residents. Another activity, implemented through a Humans in Harmony chapter at Columbia University Medical Center, paired health professional students with patients in palliative care support groups. Ethnographic observations and participant interviews revealed that engagement in interpersonal processes aligned with a capabilities-informed approach which emphasised social reciprocity, well-being, and flourishing. Moreover, evaluations of the activities through pre- and post-program measures supported a hypothesis of enhancement of interpersonal closeness and in attitudes about empathy and care. Such participatory approaches may offer new frameworks for the application of the arts in response to current geopolitical and cultural challenges.