Screening for any disease is generally reserved for situations in which the disease itself is serious, the treatment before event onset is more effective than treatment rendered after an adverse event, and when the prevalence of the disease during the detectable preclinical phase is high. Atrial fibrillation (AF) is the most common sustained arrhythmia in adults and carries a risk of significant morbidity and mortality, especially an increased risk of stroke. Oral anticoagulation for primary prevention of stroke is preferable to the consequences of stroke itself, particularly in patients with AF in whom stroke is more often fatal or disabling compared with non-AF stroke. An effective screening program also requires that the technique have a high positive predictive value, exposes the individual to minimal risk, and presents an acceptable economic burden to the patient and health care system. Most would agree that as a disease, AF fulfills the requirements or desired circumstances for screening. However, the best method of AF screening remains a matter of debate.