A study was carried out on 27 patients (22 women and 5 men) suffering from gallbladder carcinoma confirmed through surgery or autopsy. The examinations were performed with a real-time scanner and 3.5 MHz transducer. Lately, higher resolution transducers (5 MHz and 7.5 MHz) have been employed which have proven more effective due to their improved resolution. The importance is stressed of scanning patients in different positions in order to allow stones and echogenic material to redistribute inside the gallbladder. A correct diagnosis was obtained in 20/27 cases. Bile duct metastases were correctly evaluated by US in 13/13 cases; liver metastases in 25/27 patients. US proved unreliable in those cases where lymph nodes were involved (0/4). Six patients underwent scanning few months, or even years, before the onset of the symptoms. Three patients presented with fundic tumors, whose wall thickening and shadowing of the external wall had been incorrectly evaluated. In the other 3 cases the gallbladder was filled with stones and had thick and constricted walls. There was only a case of invisible carcinoma. Gallbladder carcinoma has often an unfavorable prognosis due to its being diagnosed in an advanced stage. The prognosis of such patients can be improved through an earlier US diagnosis only. The first step in this direction seems to be the identification of the precursor lesions.