The authors identified a pathological fear of methadone detoxification in 22%, 25%, and 32% of random samples of patients in three disparate methadone maintenance programs. Patients with a pathological fear of detoxification had higher scores on the Detoxification Fear Survey Schedule, had longer histories of addiction, had been addicted for a larger percent of their life spans, and were older than patients without this fear. A greater proportion of the female patients had this fear, and a greater proportion of the patients with this fear had drug-free urinalyses. The authors recommend the use of the Detoxification Fear Survey Schedule as well as intervention to help rehabilitated opioid addicts initiate and complete detoxification.