Interest exists in assessing health-related quality of life as one aspect of treatment effectiveness with substance abuse clients. The SF-36 Health Survey is a self-report measure assessing subjective health status along physical and mental health dimensions. Subjects were 252 adults in an outpatient, randomized clinical trial for substance abuse treatment. Subjects reported significantly more impairments in functioning when compared to U.S. population norms, but differences disappeared after three months of treatment. There was little support that quality of life functioning was significantly related to substance use during treatment. Results highlight the importance of using the SF-36 to facilitate treatment planning.