Aim. The aim of this study was to analyze the effectiveness of intensive (150–210 sessions), short-term (10–14 weeks) group psychotherapy in the treatment of neurotic disorders, and selected personality disorders.

Methods. The study involved 145 patients treated in day hospital due to neurotic disorders and selected personality disorders. The measurements were performed twice–at the beginning and at the end of hospitalization. The effectiveness of psychotherapy in the reduction of symptoms of neurotic disorders was measured with symptom checklist “0”. The change in the severity of personality traits characteristic for neurotic disorders was examined using Neurotic Personality Questionnaire KON-2006. Results. A significant reduction in symptoms of neurotic disorders was found in 84% of patients (85.7% women and 80.8% men). 70.3% of the examined patients obtained in the measurement at the end of treatment results indicating the level of severity of neurotic disorders symptoms below the cut-off point separating population of healthy individuals from patients. A significant reduction in the severity of personality traits characteristically occurring in patients suffering from neurotic disorders was found in 76% of patients (74.5% women and 78.7% men). 42.8% of the examined patients obtained in the measurement at the end of the treatment the value of neurotic personality traits index (X-KON) typical for healthy population. Conclusions. Intensive, short-term group psychotherapy with elements of individual therapy is an effective treatment for neurotic disorders. The majority of treated persons obtains a significant symptomatic improvement and a reduction in the severity of neurotic personality traits.