This article reviews and summarizes the pathophysiology, risk factors, and the management of arrhythmias in patients undergoing noncardiac thoracic surgery.Cardiac arrhythmias are common findings in the perioperative period, particularly with increasing age. They often complicate the course of the patient's recovery after operation. The most common postoperative arrhythmia is atrial fibrillation. It requires either a rate or rhythm control strategy, and the need for anticoagulation has to be assessed depending on the duration of the arrhythmia and risk factors. Fortunately, malign sustained ventricular tachyarrhythmias (ventricular tachycardia, ventricular fibrillation) are rare. Acute treatment and, in the absence of a reversible cause, a long-term preventive strategy may be warranted. Transient bradyarrhythmias can be managed by atropine or with temporary pacing.Arrhythmias are common after thoracotomy. Physicians treating patients with postoperative arrhythmias should bear in mind that arrhythmia management does not only comprise a specific therapy for the arrhythmia itself, but also includes the correction of transient and correctable predisposing and causative factors.