Abstract
Two procedures were used to treat tics in a psychotic patient who also had many severe behaviour problems. The first step in the treatment consisted of a technique based on positive reinforcement and punishment. Applying this technique, the tics were almost eliminated at the termination of the first session. However, the withdrawal of this technique at the thirteenth session resulted in a significant increase in the frequency of tics. A technique based on stimulus control begun at the fourteenth session and continued until termination of the treatment resulted in a progressive decrease in the rate of tics. At the seventeenth session, the withdrawal of this procedure did not cause an important increase in the frequency of tics. This technique was used until the tics disappeared entirely. A two-year follow-up revealed that the patient was free of the symptoms.