Research on the implementation of smoking cessation counseling within substance abuse treatment organizations is limited. This study examines associations among counselors' implementation of therapy sessions dedicated to smoking cessation, organizational factors, and counselor-level variables. A two-level hierarchical linear model including organization- and counselor-level variables was estimated using survey data collected from 1,794 counselors working in 359 treatment organizations. Overall implementation of smoking cessation counseling was low. In the final model, implementation was positively associated with counselors' knowledge of the Public Health Service's clinical practice guideline, perceived managerial support, and belief that smoking cessation had a positive impact on recovery. Private versus public funding and presence of a formal smoking cessation program were organization-level variables which interacted with these counselor-level effects. These results highlight the importance of organizational contexts as well as counselors' knowledge and attitudes for effective implementation of smoking cessation counseling in substance abuse treatment organizations.