In Denmark, approximately 4500 persons suffer yearly from an out-of-hospital cardiac arrest with mortality close to 100%. The principal arrhythmia is ventricular fibrillation, which can only be treated effectively with prompt external defibrillation. Automatic external defibrillators (AED) are small, portable, easily operated devices. They have documented high specificity and sensitivity. Moreover, biphasic automatic external defibrillators are at least as effective as traditional monophasic defibrillators. Survival rates with good neurological status as high as 60% have been reported. Better survival of out-of-hospital cardiac arrest victims requires, however, improvements throughout the chain of survival, not only more automatic external defibrillators. Therefore, the health care system has to discuss thoroughly and solve important questions regarding organisation, logistics, education, and legal aspects in order to improve survival for out-of-hospital cardiac arrest victims.