Therapeutic factors in group psychotherapy could result with symptomatic, behavioral, and personality changes. According to Yalom (1985), therapeutic factors are: instillation of hope, universality, imparting of information, altruism, the corrective recapitulation of the primary family group, development of socializing techniques, imitative behavior, interpersonal input, interpersonal output, group cohesiveness, catharsis and existential factors. Their importance varies during group process.

Although therapeutic factors of group psychotherapy with nonpsychotic patients are well investigated, there are few studies regarding group psychotherapy with psychotic patients.

In this paper we will present investigation of therapeutic factors by Yalom's questionnaire in different phases of group psychodinamic oriented psychotherapy with psychotic patients, respectively in patients who have participated in gruop psychotherapy for less than six months and in those that have participated in group psychotherapy for more than five years. We expect the results of this study to contribute to better understanding of group process with psychotics and to the development of guidelines for the definition of more specific therapeutic strategies.