Relevance.The effects of self-organization of subjects and groups in their joint activities are not well understood. The purpose of the work is to analyze and systematize the facts of manifestations of self-organization in the professional activity of people in a limited social space and historical time (in organizations, in a profession, in professional specialization, etc.).

Objectives. 1) A description of the facts of self-organization as a phenomenon of “psychological niches” in the models of the labor activity of subjects in similar and in different areas. 2) Identification of the determinants of the effects of self-organization of human activity.

Method. Analysis and synthesis of diagnostic data by the method of 16 PF R.B. Cattell, more than 700 professionals (drivers, private security guards, heads of departments of large industrial enterprises) obtained in the author’s studies (1994–2017), and more than 400 civil servants in the diagnostic data in 1995 and 2000, by the method of 16 PF.

Results. It is shown that the personal characteristics of the subjects are associated with their professionally important qualities, typical psycho-physiological states, value orientations, and meanings of work. Self-organization in the professional activity of individual subjects and groups as a phenomenon of “psychological niches” is a manifestation: not of a single, but of a particular and typical; the multi-level relationship of social, psychological and biological adaptation mechanisms of interacting people in a dynamic social environment; “Multipolarity” of high activity areas of subjects, time consistency of periods of their interactions; effects that are more evident not in the productivity of people’s work, but in satisfaction with it, etc.

Conclusion. Finding ways to manage the processes of group self-organization of labor subjects, enhancing the positive effects generated by human interactions, and stopping (weakening, correcting) negative ones can contribute to the development of new resources for increasing the productivity of individual and collective labor.