Clinical evidence suggests the possibility of conditioning of narcotic abstinence symptoms. Addicts report subjective and objective signs of withdrawal/craving when exposed to certain stimuli. This may partially explain the high rate of relapse to drug seeking behavior when treated addicts return to their home environment. Conditioning of narcotic abstinence symptoms was produced experimentally in five of eight volunteer subjects. Brief naloxone precipitated abstinence was the unconditioned response. The conditioned stimulus was a tone and odor. After an average of seven training trials, the tone and odor produced a conditioned abstinence response. The conditioned response consisted of subjective components (feelings of sickness, nausea, cramps, craving) and objective components (yawning, tearing, rhinorrhea, irregular respiration and transiently increased blood pressure). These laboratory findings support the anecdotal evidence regarding the existence of conditioned abstinence phenomena.