Interest in sudden unexpected and unexplained death in individuals with epilepsy (SUDEP) was rekindled in the United States by Jay and Leestma during the early 1980s and more recently by antiepileptic drug (AED) trials and medicolegal issues. The incidence of SUDEP has been and is being evaluated in North America and the United Kingdom. Specific criteria for the classification of definite, probable, possible, and unlikely SUDEP implemented in United States epidemiologic studies are presented. Evidence for the increased relative risk for sudden death in epilepsy compared with the general population is also discussed.