Rationale: There is little information about long-term relapse patterns for cigarette smokers. Objective: To describe long-term prevalence of relapse and related smoking patterns by sex, race, age, and education level among a community-based cohort of young adults followed for 25. years. Methods: We examined 25. years of data from Coronary Artery Risk Development in Young Adults (CARDIA), an ongoing study of a community-based cohort of 5115 men and women aged 18 to 30. years at baseline with periodic re-examinations. At each examination smoking, quitting, and relapse were queried. We examined prevalence of smoking relapse among 3603 participants who attended at least 6 of the 8 examinations. Results: About 53% of 3603 participants never reported smoking on a regular basis. Among the remaining 1682 ever smokers, 52.8% of those who reported current smoking at baseline were still smoking by the end of the study, compared to 10.7% of those who initiated smoking by year 5. Among those classified as former smokers at baseline, 39% relapsed at least once; of these, 69.5% had quit again by the end of the study. Maximum education level attained, age at study baseline, and race were associated with failure to quit smoking by the end of the study and relapse among those who did quit. Maximum education level attained and age at study baseline were also associated with ability to successfully quit after a relapse. Conclusions: Smoking relapse after quitting is common, especially in those with lower education level. Education was the strongest predictor of all three outcomes. Improvements in access to treatment and treatment options, especially for underserved populations, are needed to prevent relapse when smokers quit.