Background. Smoking cessation after myocardial infarction (MI) has been associated with a 50% reduction in mortality but in-hospital smoking cessation interventions are rarely part of routine clinical practice.Methods. One hundred cigarette smokers consecutively admitted during 1996 with MI were assigned to minimal care or to a hospital-based smoking cessation program. Intervention consisted of bedside cessation counseling followed by seven telephone calls over the 6 months following discharge. Primary outcomes were abstinence rates measured at 6 months and 1 year post-discharge.Results. At follow-up, 43 and 34% of participants in minimal care and 67 and 55% of participants in intervention were abstinent at 6 and 12 months. respectively (P < 0.05). Abstinence rates were calculated assuming that participants lost to attrition were smokers at follow-up. Intervention and self-efficacy were independent predictors of smoking status at follow-up. Low self-efficacy combined with no intervention resulted in a 93% relapse rate by 1 year (P < 0.01).Conclusions. A hospital-based smoking cessation program consisting of inpatient counseling and telephone follow-up substantially increases smoking abstinence 1 year after discharge in patients post-MI. Patients with low self-efficacy are almost certain to relapse without intervention. Such smoking cessation programs should be part of the management of patients with MI.