Postoperative atrial fibrillation is associated with significant morbidity, longer hospital stay, and higher related costs. Although the etiologic mechanism of postoperative atrial fibrillation and its optimum method of prophylaxis or management are not well defined, progress has been made during the past decade. This review focused on recent findings leading to a better understanding of the mechanisms and management of atrial fibrillation after surgery and current approaches directed at prevention of thromboembolic sequelae. Because postoperative atrial fibrillation is a frequent complication, preoperative risk assessment algorithms are being proposed to minimize the number of patients in whom an intervention to prevent atrial fibrillation is undertaken, and thus, reduce toxicity due to antiarrhythmic drug therapy. Finally, current data suggest that once atrial fibrillation has occurred, a rate-control strategy during the first 8 to 12 hours is reasonable because 50% of those episodes will resolve during this period. Beyond this period, a more aggressive approach using class IC or III antiarrhythmic drugs will hopefully reduce the number of patients requiring anticoagulation and prolonged drug therapy.