Addiction to opioids causes major medical, social, and economic problems to both the individual and society. Opioid dependence is defined as a strong desire to use the substance, difficulty in controlling its use, the presence of a physiological withdrawal state, tolerance of the use of the drug, neglect of alternative pleasures and interests and persistent use of the drug, despite harm to oneself and others. It is a complex disease involving physiological, psychological, genetic, behavioral and environmental factors. In Canada, it is estimated that there were more than 80,000 regular illegal opioid users in 2003. The number of illegal drug-related overdose deaths in Canada was 958 in 2002. Opioid dependence is related to the abuse of not only illegal opioid drugs (e.g. heroin), but also some of the most commonly prescription drugs, such as codeine-containing Tylenol, hydromorphone, oxycodone, morphine and others. Treatment of opioid dependence includes three approaches: stabilization, detoxification and maintenance. Stabilization is usually achieved by opioid substitution treatments to ensure that the drug use becomes independent of mental state (such as craving and mood) and independent of circumstances (such as finance and physical location). The next stage is detoxification that is to withdraw from opioids. The final step is maintenance to prevent relapse. Detoxification refers to the process by which the effects of opioid drugs are eliminated in a safe and effective manner, such that withdrawal symptoms are minimized. Appropriate use of the detoxification agents plays a crucial role in increasing the successful detoxification rate, while minimizing the side effects and withdrawal symptoms. Methadone (μ-opioid receptor agonist) or buprenorphine (μ-opioid receptor agonist and κ-opioid receptor antagonist) are recommended first-line treatments in opioid detoxification. Naloxone is an opioid antagonist without agonist properties. In opioid-dependent patients, naloxone precipitates withdrawal. Suboxone (buprenorphine/naloxone) was approved by Health Canada in 2007 for substitution treatment in opioid drug dependence in adults. It is a fixed combination of buprenorphine (a partial μ-opioid receptor agonist) with naloxone (an opioid antagonist) in a 4:1 ratio. The addition of naloxone to buprenorphine is expected to decrease the intravenous abuse of buprenorphine, because when taken sublingually, absorption of naloxone is minimal, however it can rapidly precipitate opioid withdrawal when injected. Suboxone is recommended for the treatment of opioid dependence for patients in whom methadone is contraindicated (such as patients at high risk of, or with QT prolongation, or hypersensitivity to methadone). The purpose of this review is to provide evidence on the comparative clinical effectiveness and cost-effectiveness of use of Suboxone compared with methadone, for the treatment of patients with opioid dependence. Subgroups such as children and pregnant women may also have access to opioids thus, the clinical benefits and risks of Suboxone for these patients will be examined as well, when evidence is available.