Background: Identifying effective relapse prevention interventions is a vital step to help smokers maintain abstinence for the long term. Aims: The purpose of this study is to determine if providing recently quit smokers with self-directed relapse prevention booklets is effective at maintaining abstinence after intensive group smoking cessation treatment. Method: Two hundred and twenty-five participants were randomized to receive Forever Free (FF) relapse prevention booklets or a control booklet (Surgeon General's report, SG) at the end of a 6-week group treatment program. Participants were then contacted by phone to assess whether they had read the materials. Smoking status was assessed 6 months after their target quit date. Primary analyses focused on the 115 participants who quit at the end of treatment. Results: There was no difference in the 6-month quit rate between groups (40.7% quit FF vs. 44.6% quit SG, p = .67). The FF group read a significantly smaller proportion of the materials versus the control booklet (20.0% read most or all of FF vs. 72.0% of SG, p < .001). Conclusion: Forever Free self-directed relapse prevention booklets did not reduce relapse or enhance cessation over general tobacco and health information when added to intensive group smoking cessation treatment. However, this study lacked power to detect a small but clinically meaningful positive effect.