Clinical supervision is an essential component of psychotherapeutic practice. However, the literature suggests that the provision of supervision in the public sector has been declining significantly over the past two decades, suggesting that many health care professionals are receiving neither the guidance nor support needed to deliver safe and effective care. Identifying the distinct challenges of supervision in the public sector and proposing prospective solutions is, therefore, a burning issue. In this article, we introduce a novel analytical framework for clinical supervision-the MATRIX-striving to address the unique demands of psychotherapy in the public sector. Various applications of this framework are thoroughly presented and further exemplified using a case illustration. We conclude by discussing the contribution of MATRIX-aided supervision to the acquisition of expert performance in psychotherapy, while also addressing its limitations. Impact StatementMost mental health care systems around the world are facing a chronic lack of resources and are struggling to provide their employees with appropriate supervision. Hence, there is a growing concern that many health care professionals are not receiving the support needed to deliver safe and effective treatment. This article introduces a novel aiding tool for clinical supervision-the MATRIX, striving to optimize the cost-effectiveness of supervisory process. Various applications of this tool are presented, as well as its unique benefits for psychotherapy in public settings.