Introduction:
Psychotherapy is a method of treatment for mental disorders of empirically varied effectiveness. . In some patients clinical improvement does not occur. Research on psychotherapy should be focused on recognition of determinants of success and failure in treatment. The goals of the study are: 1) a description of the process and results of long-term client contribution oriented integrative psychotherapy with patient suffering from obsessive-compulsive disorders (OCD), who had enduring difficulties in beneficial participation in psychotherapy; 2) a psychological analysis of change mechanisms and factors influencing the improvement.

Material and Methods:
Case study of psychotherapy process

Results:
An example of clinical effectiveness of the therapeutic interventions based on referring to the patients’ experiences of self-effective involvement in psychotherapy and provoking such experiences A positive coincidence between patient’s experiences of shaping the process of therapy and the results of treatment was recognized. Psychological analysis of change mechanisms was done from the integrative perspective.

Conclusions:
The recognition and intentional activation by the therapist the patient’s personal potential for change can increase effectiveness of psychotherapy of persons with enduring obsessive-compulsive disorders, eating and depressive disorders