The dependence syndrome concept, developed for alcohol and extended to other abused substances, postulates that its elements form a continuum of severity. Dependence severity should predict treatment success if this concept has predictive validity. Because most studies that examined this aspect of validity used alcoholic populations, we undertook the present 1-year follow-up of 48 opiate addicts to investigate whether dependence severity predicted program retention, treatment compliance, and psychological functioning. We also controlled demography, withdrawal severity, and substance use frequency. The best predictor of program retention was the addicts' rating of substance use frequency. Severity of opiate dependence predicted program retention in White addicts only. For non-White opiate addicts, concurrent depression and cocaine abuse had much greater association with program retention compared to dependence severity.