This is a rare condition, often presenting late as a result of compression of adjacent organs, as demonstrated by radiological examinations. Laparoscopy reveals only hepatic hypertrophy whilst the intrahepatic lesion is seen on isotope scan, its irregular appearance sometimes leading to confusion with metastatic disease. Study by scanner confirms its cystic nature. This dysembryoplasic nature of this lesion is now generally accepted, its origins lying in the vestiges of the hepatic ducts. Resection of the overling dome is the usual treatment of exteriorised biliary cysts. The evacuation of large central cysts may be associated with haemorrhagic complications as a result of decompression, which explains the need for slow evacuation or even the preference sometimes expressed for excision at the outset, in particular in the case of a left-sided lesion.