Compares the performance of substance dependent individuals vs healthy subjects using a decision-making task (the Game of Dice Task or GDT) which presents explicit and stable rules for gains and losses. Participants were 18 clean, opiate dependent (OD) individuals void of withdrawal symptoms and a control group (CG) of 18 healthy comparison subjects without a history of drug abuse. Measures included neuropsychological test battery and personality assessments as well as the revised Freiburg Personality Inventory (FPI). Results showed that the OD group performed inferior to the CG in various neuropsychological tasks as well as in the GDT itself. Results indicate that OD patients show decision-making reductions with a preference toward risky decisions which in turn lead to negative consequences in the long run. Also, performance on a decision-making task such as the GDT is found to be related to executive functioning and feedback processing in OD patients. Further studies should investigate decision making under risk conditions in different subgroups of patients with OD living in various environments.