An open system model for psychotherapy evaluation

An open system model, constructed with concepts from general systems theory and cybernetics, is presented and applied to the psychotherapy process and to the evaluation of patient change. It is asserted that the patient-therapist system and the patient's social system operate interdependently, exchanging mutual causal effects. To initiate change the therapist must introduce negative feedback within a range of patient toleration. Once change is initiated, the crucial determinant is the response by the social system to the input of new information. Thus patient change is a function of both the therapist and the social system. Implications for research are discussed.where he coordinates community psychology training within the clinical doctoral program.