The purpose of this philosophical inquiry was to argue for the integral importance of the therapeutic relationship within a neuroscience-informed approach to music therapy practice. A preliminary review of the music therapy literature revealed that the therapeutic relationship is important for the following reasons: the therapeutic relationship (a) provides a safe environment integral to the music therapy process; (b) enhances motivation and engagement through a collaboration between the client and music therapist; and (c) informs the active individualization of music therapy interventions. An initial review of the literature included an exploration of the neuroscience-informed music therapy literature and the importance of the therapeutic relationship in music therapy practice. The neuroscience-informed music therapy literature was analyzed using the aforementioned reasons to investigate why the therapeutic relationship is important within the approach. Findings of the analysis provided evidence of the importance of the therapeutic relationship within neuroscience-informed music therapy, as well as preliminary conceptualizations of the relationship using existing neuroscience-informed clinical protocols. Perspectives from social neuroscience, interpersonal neurobiology, music neuroscience, and music therapy were integrated throughout the research thesis to provide music therapists working from a neuroscience-informed approach with the language to articulate the importance of the relational elements of their work. Recommendations for future research are presented.