Abstract: The purpose of this study was to examine the effects of Neuro-Linguistic Psychotherapy on psychological difficulties and perceived quality of life of clients who came for psychotherapy during free practice. Method: A total of 106 psychotherapy clients were randomly assigned to a therapy group or a control group. The outcome was assessed by the Structured Clinical Interview for DSM-IV Personality Disorders (SCID II) with respect to clinical symptoms and by the Croatian Scale of Quality of Life (KVZ) with respect to Quality of Life. The therapy group received the measures at pre-, post- and five-months follow-up occasions, whereas the control group received them initially and after a period of three months. Results: In the therapy group, as compared to the control group, there was a significant decrease of clinical symptoms and increase in the quality of life. With respect to clinical symptoms, effect sizes were 0.65 at post-measurement and 1.09 at follow-up, indicating a substantial reduction of symptom strain, which is comparable to the well established effects of Cognitive Behavior Therapy. We also found a significant increase in perceived quality of life after therapy, as compared to the wait-list control group, with effect sizes between 0.51 and 0.73. Therapeutic improvements were still present five months after the end of therapy, showing further development in the same direction. Conclusions: Neuro-linguistic psychotherapy is an efficient intervention, which is on a par with other, well-established psychotherapeutic techniques.