The aim of the study was to evaluate the role of contrast-enhanced ultrasound (CEUS) in the characterisation of focal liver lesions and for the selection of surgical patients. One hundred and thirty-five consecutive patients (71 women, 64 men) with 165 focal liver lesions (mean size: 3.1 cm)--89 benign (10 simple cysts, 26 haemangiomas, 29 focal nodular hyperplasia, 2 hepatocellular adenomas, 11 focal fatty sparing, 3 focal fatty areas, 5 regenerative nodules, 2 hydatid cysts, 1 abscess) and 76 malignant (47 metastases, 26 hepatocellular carcinomas and 3 peripheral cholangiocarcinomas)--underwent CEUS after the administration of SonoVue. Two radiologists reviewed baseline US and CEUS scans obtained 25-30 sec (arterial phase), 55-80 sec (portal-venous phase), and 235-260 sec (late phase) after initiating SonoVue injection, respectively. The radiologists classified each lesion as malignant or benign on the basis of clearly defined diagnostic criteria. Sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy were calculated. CEUS correctly characterised 156/165 focal liver lesions (94.5%), 85 benign and 71 malignant. Five focal liver lesions (3%; 3 haemangiomas and 2 hepatocellular carcinomas) remained undetermined after CEUS and 4 focal liver lesions (2.4%; 3 hepatocellular carcinomas and 1 abscess) were misdiagnosed. CEUS presented sensitivity, specificity, and diagnostic accuracy values of 93.4%, 95.5% and 94.7% respectively. Positive and negative predictive values were 94.7% and 94.4%, respectively. CEUS is a useful tool in the characterisation of focal liver lesions and for selecting surgical patients.