We examined prospectively a series of 150 children with epilepsy beginning in the first year of life. We classified the types of epilepsy into five categories: West syndrome, other epileptic encephalopathies, generalized, partial and undetermined epilepsies. Of 150 patients, 15 died; 135 were followed for at least 4 years. In order to define possible factors influencing prognosis we evaluated neurological and cognitive outcome and made percentage comparisons between groups, for aetiology, age of onset, family history of epilepsy, and psychomotor development before onset. Epileptic encephalopathies as well as the symptomatic forms of West syndrome showed a very poor neurological and cognitive outcome. As previously recognized, only cryptogenic forms of West syndrome had a benign prognosis. For the generalized epilepsies, analysis of different factors, namely late age at onset, cryptogenicity and absence of primary cognitive impairment, indicated a good prognosis. In contrast, partial epilepsies usually had a poor outcome, irrespective of the aetiology, whether cryptogenic or symptomatic.