The evaluation research on traditional medical model treatment shows high drop-out and relapse rates along with limited impact on polydrug users. Outdoor challenge programs have been used as an alternative strategy within the context of Opponent-Process theory and the therapeutic use of stress. The Opponent-Process theory assumes that for some reason the brains of all mammals are organized to oppose or suppress many types of emotional arousals or hedonic processes, whether they are pleasurable or aversive. As this theory applies to addiction, a critical juncture in the development of addiction occurs when the substance user realizes that withdrawal symptoms can be averted by self-dosing. Wilderness programs may help overcome addiction by building confidence in abusers that they can overcome stressful events. By guiding participants through challenging events and activities, wilderness programs produce improved self-esteem, stress-management skills, group cooperation, and improved physical health. Poor coping skills and low self-esteem contribute to substance abuse. Attitudinal and behavioral changes that result from learning under positive stress may be potent, generalized, and long-lasting. 37 references