The aims of this article are multifaceted: to change the ideas about the traumatic nature of supervision, to reveal its potential in the development of young specialists, to preserve and maintain professional identity among experienced psychologists, and to develop supervision as an integral part of the full-fledged activity of practising psychologists and specialists in the helping professions in Kazakhstan. The article is devoted to the analysis of the main definitions of professional thinking which are developing in the setting of group multimodal supervision. Based on the analysis, three definitions were identified – the unity of affect and intelligence, theoretical thinking, and the principle of differentiation. The article shows the importance of the development of these definitions of professional thinking among practising psychologists, and describes the features of the development of these definitions in group multimodal supervision. The following definitions of thinking were identified in the course of data analysis: the unity of affect and intelligence, theoretical thinking, and the principle of differentiation. These definitions productively describe what professional competencies are formed in the process of supervision by a specialist. The described competencies of professional thinking fill in the existing gap of knowledge in this area, showing how the experience of supervision in the multimodal supervision group works towards the establishment of professional identity, and what specific mental competences are developing. It is worth noting that this is the first experience of highlighting the formation of the definitions of professional thinking. The study is based on the following theoretical traditions in psychology: general psychology, psychoanalysis, and professional multimodal model of supervision.