Objective: This study examined the role of depressive symptoms in the context of specific demographic and individual treatment characteristics in predicting drug abstinence at discharge from outpatient substance abuse treatment. Methods: Data from 827 clients entering a large public funded outpatient substance abuse treatment program were analyzed using logistic regression to assess the effects of depressive symptoms on drug abstinence status at discharge. Analyses on the effects of gender, race, age, education level, frequency of drug use, insurance status, referral source, and length of stay in treatment on drug abstinence status at discharge were also conducted. Results: Higher depressive symptom scores significantly predicted a decreased likelihood of clients' abstinence at discharge even after accounting for other significant demographic and treatment variables such as insurance status, race, age, primary drug of choice, frequency of drug use at admission and length of stay in treatment. Conclusion: The findings suggest that depression symptoms are an important factor affecting successful substance abuse treatment outcomes. Treatment approaches that address depressive symptoms are likely to enhance substance abuse treatment outcomes in real world clinical settings. (c) 2005 Elsevier Inc. All rights reserved.