Objectives: To investigate the change process and the effectiveness of five sessions of Family Constellations (FC) using mixed methods in mixed settings (videoconference and in person). Methods: This single case study used a triangulation of evaluation methods:; quantitative (EADS-21) and qualitative: the notes from the consultations, and the service user's responses to the Psychotherapeutic Process Data Mining Questionnaire (PPDMQ). This mixed methods exploratory design provided a set of specific information associated with the change process and the outcomes. Results: The service user’s depressive symptomatology went from a severe level to normal, and the results of the post-test remained at follow-up (after three months). The severe depression seems to have been mitigated through interventions that fomented contact with reality, self-determination, the psycho-emotional establishment of systemic places, and meeting of meanings for autobiographical events. Conclusions: This paper may stimulate further studies that use the PPDMQ to create metasynthesis and that gauge whether FC can, as a systemic, intergenerational, and integrative psychotherapy, contribute to enriching the body of psychotherapies, based on scientific evidence, whosewhereby its effectiveness may mitigate the global escalation of depression.