Music therapists focus on the interaction between client and therapist and how listening and creating music works within the therapeutic relationship to achieve therapeutic goals. The client is the primary focus of most case study research on the practice of doing therapy, centering on moments of interest in the therapy progress. In addition, there is now a well-documented body of evidence consisting of Cochrane reviews, systematic reviews, and scoping reviews on the effect of music therapy (MT) on outcome measures. However, neuroscience-informed process research into the mechanisms of change in MT is still underdeveloped. For that, research might benefit from naturalistic designs investigating (social) cognitive-affective processes and embodied cognition in situ.