Intraoperative echography helps both in the detection of the tumor and in the assessment of the vascular and biliary anatomy. The experience reported here was gained with 114 carcinomas in cirrhotic livers, 46 carcinomas in normal livers, 330 cases of metastases to the liver and 55 benign tumors. Ultrasound has modified the surgical prediction in 10 to 30% of all cases, according to the group.