Heartwatch is an Irish primary care-delivered secondary prevention program for patients with established coronary artery disease (CAD). We aimed to describe the patterns of smoking cessation in Heartwatch and examine the associates of successful smoking cessation. Participants with established CAD were invited to baseline and three-monthly clinic visits. Data on all persons reporting tobacco use at baseline were examined. Associations between smoking cessation and baseline factors were examined using logistic regression models. Data were available on 1,679 Heartwatch patients who were smoking at first visit. One third of smokers (581 participants: 34.6%) achieved smoking cessation during the study period (2003 to 2007), 80.4% of whom remained nonsmokers at end of follow-up. Positive associates of successful smoking cessation included increasing age, male sex, a body mass index > 25 and increasing number of study visits. Negative associates included having a means-tested general medical services allocation, being unemployed, and documentation of stop-smoking advice. All factors except employment status retained statistical significance when examined in a multivariable model. In conclusion, high levels of smoking cessation were achieved in this secondary prevention population of persistent smokers. Associates of successful smoking cessation were identified. Specific stop-smoking strategies should be considered for those subpopulations less likely to quit.