Both heroin-addicted individuals and methadone maintenance patients are likely to face untreated opioid withdrawal while incarcerated. Limited research exists concerning the withdrawal experiences of addicted inmates and their impact on individuals' attitudes and plans concerning drug abuse treatment. In the present study, 53 opioid dependent adults (32 in methadone treatment and 21 out of treatment) were interviewed in an ethnographic investigation of withdrawal experiences during incarceration. When treatment for opioid withdrawal was unavailable, detoxification experiences were usually described as negative and were often associated with a variety of unhealthy behaviors designed to relieve withdrawal symptoms. Negative methadone withdrawal experiences also negatively influenced participants' receptivity to seeking methadone treatment upon release. A minority of participants took a positive view of their withdrawal experience and saw it as an opportunity to detox from heroin or discontinue methadone. Findings support the importance of providing appropriate opioid detoxification and/or maintenance therapy to opioid-dependent inmates.