The accuracy of ultrasonographic diagnosis of hypoechoic focal fatty change in the 'bright liver' was evaluated in 40 lesions found in 35 patients followed up for a mean period of 37.8 months. Patients with ultrasound and laboratory findings suggesting liver cirrhosis were excluded from the study. All patients underwent a blind liver biopsy in order to verify the diagnosis of diffuse disease suggested by the finding of 'bright liver'. No guided biopsy was performed on the focal lesions in order to establish the accuracy of ultrasound alone in recognizing focal fatty change. Clinical, haematologic and echographic follow-up confirmed the diagnosis in all cases. All histological specimens revealed liver steatosis, indicating a 100% sensitivity of ultrasonography in identifying non-cirrhotic fatty liver with an accompanying focal change. Increased echogenicity and hypoechoic focal changes are reliable indicators of fatty infiltration, making ultrasonography an acceptable, non-invasive method for the diagnosis of liver steatosis.