This article describes the development of a research procedure including a musical framework, to explore, describe and illuminate intersubjective exchanges in child psychotherapy. Applying a qualitative explorative approach, musical parameters were studied and analysed within an intersubjective framework, in selected samples of emotion regulation with children in time-limited intersubjective psychotherapy. The resulting multilayered microanalytic method is illustrated through one example and discussed in light of the research questions. Through exploring musical parameters from second to second as focal points within a multilayered analysis, such parameters seemed to embody the child’s feelings and intentions as well as organize intersubjective exchanges. The concept of musical dynamics is suggested as a description of lived relationship experiences over time.