Sudden cardiac death (SCD) remains a major public health problem in developed countries. Nonetheless, the last two decades have witnessed many advances in the epidemiology of SCD, its prediction and prevention. We have learned that approximately half of these events occur in individuals without a previously diagnosed heart disease. The proportion of the presenting arrhythmia in patients with cardiac arrest has somewhat changed from ventricular fibrillation towards pulseless electrical activity and asystole. These observations, if further confirmed, may challenge previous strategies of risk stratification and the management of survivors of cardiac arrest. Despite efforts to identify patients with clinical, anatomic, autonomic, electrical, and/or transient risk factors, the predictive accuracy of relevant diagnostic tests remains often inconclusive. Further progress in this field can be expected by imaging studies that are playing an increasing role in identification of high-risk patients. There have been major advances in the understanding of the role of genetics and we have clearly entered in an era in which knowledge of the genotype will contribute to a better individualization of the management of patients at risk for life-threatening arrhythmias of genetic origin.