Nonpharmacological treatment for atrial fibrillation (AF) has evolved dramatically over the past 20 years. Pulmonary vein isolation, a catheter ablation technique developed in the last decade, prevents focal triggers in the pulmonary veins from initiating episodes of AF. Although the procedure initially involved focal ablation with a catheter directly in the pulmonary veins, investigators subsequently found that isolating the pulmonary veins by applying ablation energy at their junction with the left atrium is more effective. After the procedure is performed once or twice, it is 70% to 80% successful in preventing recurrence of AF episodes in the first year of follow-up. The pulmonary vein isolation procedure is most suitable for patients whose recurring symptomatic episodes of AF have not been suppressed by antiarrhythmic drugs or who do not wish to take long-term antiarrhythmic or anticoagulation medications. The procedure is more successful in patients with intermittent (paroxysmal) AF than in those with long-standing, continuous (chronic) AF.