In a wide range of psychological approaches, a situational approach, which has received theoretical justification in domestic studies, is promising. The central concept of “situation” is defined as an indirect element between the conditions of the environment and the individual personality characteristics of the subject in the context of problems of double determination of activity. Definitions of the situation are mostly limited to the idea of a subjective image of external conditions, the adequacy of which is interpreted as a manifestation of the environmental determination of activity, while its variability is understood as the manifestation of personal determination of activity. The partiality of the image of external conditions is one of the manifestations of personal determination of the cognitive component, which does not rule out the problem of determination of activity. The purpose of the work is to justify limitation of the concept of "situation" to the subjective sphere and to interpret it as the result of integration of the determinants. The notions of the environment are clarified; the need for assessments of the interpreted image of conditions, of subject’s own resources and their balance, as well as of the "room" for appraisals and integration of the determinants, are rationalized. The situation is defined as a reflexive appraisal "model" of the relationship between the interpreted image of objective conditions and the internal state, within the limits of actual motivation, actual experience and personal preferences. The functions of the situation are the organization of activity (actual-genesis) and its regulation at the stage of execution, ensuring its stability and expediency. Possible systematization of situations based on the typology of conditions and options for their subjective assessment, the subject's possibilities and their assessment, is presented. Particular attention is paid to the situations of uncertainty, decision-making and risk; their features, psychological mechanisms and personal determinants are described. The situational approach enhances the possibilities of explaining the variability of activity in identical conditions, its sustainability in changing conditions, as well as explaining the causes of errors caused by the uniqueness of the assessments in a reflexive model of reality.