Atrial fibrillation will present the most significant arrhythmia management challenge for clinicians in the new millennium, particularly as the percentage of elderly patients and longevity increase worldwide. The clinical manifestations of the arrhythmia are wide ranging: paroxysmal to permanent modes of occurrence and asymptomatic to severely symptomatic presentations. Perhaps most important, the major risks of atrial fibrillation are stroke and death. Current therapies remain heavily focused on pharmacologic efforts to reduce the severity of primary symptoms and to prevent stroke and other thromboembolic complications by means of anticoagulation. It has not yet been proven that prevention of atrial fibrillation will prolong survival, however. Nonpharmacologic therapies remain under intense basic and clinical investigation as promising means to improve outcome further for patients suffering from atrial fibrillation.