Congenital cystic liver disease represents a rare entity and only in 5%-20% the cysts cause symptoms or complications that demand therapy. In the past decades several therapeutic approaches have been developed with variable long-term outcome. We report herein our results and the postoperative outcome of 26 patients treated from 1987 to 1998 in our department because of symptomatic or complicated congenital cystic liver disease. In cases of symptom-producing solitary liver cysts our therapy of choice was laparoscopic fenestration. In cases of adult polycystic liver disease we mostly performed partial hepatic resection and fenestration. Both therapeutic approaches have proven a favorable long-term outcome. However, some types of adult polycystic liver disease possess a high risk of reappearance. Preoperative pathomorphological assessment of polycystic liver disease should be performed to choose the operative procedure in relation to the expected recurrence rate. Because of the progresses made in dialysis therapy and transplantation surgery in patients with adult polycystic kidney disease, an increase of patients with symptomatic polycystic liver disease has to be expected in the near future.