The last 30 minutes of MC will be divided into three stages: 1) a short presentation on the cognitive deficits due to CD (Giving Information); 2) participants will report their impressions about their performance in chess linking it to real life situations such as drug-related events, difficulty monitoring and directing behavior, controlling craving and relapse (Developing Discrepancy); 3) discussions encouraging healthy decision making, focusing on future and favorable real-life long-term behaviors, as opposed to immediate and high risk behaviors (Supporting Self-Efficacy).