The prevalence of epilepsy in children aged 0-15 years of Kaunas city, Lithuania, was evaluated on 1 January 1995. Multiple sources for case identification were used, i.e. medical records at the university hospital, regional outpatient clinics and consultation centres, institutions, schools and kindergartens for the handicapped. Active epilepsy was defined as two or more unprovoked epileptic seizures with at least one seizure occurring within the previous 5 years, regardless of the antiepileptic drug treatment. Prevalence was found to be 4.25 (3.42, if age-standardized) in 1000. The highest rate was found in the 10-14 years age group. The male/female ratio was 1.29. No possible causes could be determined in 60.3% of cases. Congenital causes were diagnosed in 18.8% of cases, perinatal causes in 15.3%, traumatic causes in 2.6% and neuroinfectious causes in 2.4%. Classification of epilepsies and epileptic syndromes [Commission on Classification and Prognosis of the International League Against Epilepsy. Proposal for revised classification of epilepsies and epileptic syndromes. Epilepsia 1989; 30:389-399] revealed that 50% of cases were localization-related epilepsies, 29.9% were generalized epilepsies, 15.9% were undetermined whether partial or generalized and 4.2% were unclassifiable. Rates for idiopathic, symptomatic and cryptogenic cases are presented.