This paper contains a conceptual definition of the impression and a conceptual model of the impression formation process and its place and role in a stakeholder’s behavior in dealing with products, services or activities. The suggested system approach has been developed from a set of theories originating from decision theory, emotion theory, impression management theory, mathematical psychology and other areas. Assumptions constituting the concept are based on a synthesis and creative interpretation of conclusions found in literature and on the authors’ intuition and observations. The approach of including a benchmark set consisting of a reference point, the psychological states of “improvement beyond this point has no additional value” and “completely unacceptable”, distinguishes this model from mainstream emotion and impression theories.