Hydatid disease is quite rare in European countries outside the endemic areas. It occurs most frequently in the liver and lungs. Surgery remains the main treatment modality for hydatid disease of the liver. There is still considerable debate as to whether the best approach is conservative surgery or radical surgery in which the cyst is totally removed including the pericyst by total pericystectomy or partial hepatectomy. We report the results of our 15-year experience with this type of surgery. A series of 35 consecutive patients operated on for hydatid disease of the liver from January 1985 to December 2000 was analysed (18 women and 17 men with a mean age of 47.7 years). The most common complaints were pain (59%), hepatomegaly and intra-abdominal masses (37%). The cysts were single in 23 patients and multiple in 12, and were found in the right lobe in 21 cases (59%), in the left lobe in 9 cases (26%), and in both lobes in 5 (15%). In one patient (2.8%), concomitant extrahepatic (splenic) disease was present. The diameter of the cysts ranged from 3.5 to 20 cm (mean value: 9.5 cm). Patients were subdivided according to the kind of surgery (radical versus conservative) and period of operation (group 1: 1985-1992; group 2: 1993-2000). With the increase in surgical skills and the advent of new techniques, radical surgery (12 cystoperistectomies, 3 left lobectomies and 3 segmentectomies) came to be performed more frequently than conservative surgery in the second period (18/20 in group 2 versus in 7/15 group 1) with low complication rates, a 3.7% mortality rate and similar operative time (175 min versus 145 min) and hospital stay (16.8 days versus 19.2 days) as compared to the conservative approach. The policy of applying radical surgery whenever feasible can be implemented with acceptable morbidity and near zero mortality. Radical surgery, however, needs to be applied judiciously, and there is still an important role for conservative surgery.