MATERIAL, METHOD: Authors present the results of surgical treatment in a series of 93 patients with medically intractable epilepsy and large epileptogenic foci, in whom multilobar resections have been performed. They constituted 13% of a group of 716 patients subjected to surgery due to drug resistant epilepsy in the period 1957-1996, in the Department of Neurosurgery, Medical University of Warsaw, Poland. Patients treated with multilobar resection constituted the group, characterised by the most severe course of epilepsy, so they usually had a long seizures' history at the time of operation (more than 10 years duration of the disease in 37% of patients), albeit they were qualified to surgery at a relatively young age (mean age at the time of surgery: 16-th year of life). Trauma was the most frequent underlying aetiologic factor (perinatal trauma and other major head injury were documented in 28% and 30% of patients respectively). Morphological abnormalities of the resected brain tissue were found on pathological examination (light microscope) in 68% of patients in this series. RESULTS Perioperative mortality was 3%. At a follow-up examination (mean follow-up period 7 years postoperatively): 30% of patients were seizure free, in 13% of patients drug discontinuation was possible. In 23% of patients less than 2-3 seizures per year occurred. So totally in 53% of patients, good result of treatment was achieved (none or only very rare seizures). In 35% of patients surgery failed to control seizures' frequency. 9% of patients were lost from follow-up evaluation. CONCLUSIONS Multilobar resection (if acceptable from the clinical point of view) may be an effective treatment choice in patients with medically uncontrollable seizures and huge epileptogenic foci. This treatment modality may offer recovery from seizures or significant improvement to 53% of patients treated. The radical removal of epileptogenic foci, age of the patients higher than 18 year of life at the time of operation, focal character of EEG abnormalities and occurrence of only one type of seizures, were found to be good prognostic factors. On the other hand younger age of the patients operated, the presence of generalized slow waves in the interictal EEG recordings and the occurrence of various types of seizures, influenced adversely on the prognosis.