BACKGROUND AND CLINICAL RELEVANCE: Although the use of opioid medications has gained increasing acceptance as a treatment option for chronic pain, there is little empirical research concerning long-term outcomes with this patient population. Several important questions concerning the use of opioids have yet to be examined in controlled studies. These include: determination of the most effective dosing regime, specification of the risk factors for medication abuse, and identification of patients most likely to achieve long-term benefits. Despite the lack of empirical data, the clinical literature to date yields two general approaches to the use of opioid treatment with chronic, nonmalignant pain. The first approach dictates that due to risk of addiction, tolerance, and insensitivity to large doses, opioid medications should be carefully controlled, with minimal and stable dosing as the eventual goal of treatment. The second approach, fostered by the beneficial use of opioids in the treatment of cancer pain, maintains that risk of addiction and abuse has been exaggerated. Proponents of this approach suggest that under-medication is a significant cause of treatment failure and non-compliance in chronic pain patients, and that prescription guidelines should emphasize patients' reports of adequate relief, regardless of dosage.