In the present study the diagnostic accuracy of US-guided fine-needle biopsy was evaluated in a series of 219 abdominal lesions < or = 3 cm in diameter (21 between 0.6 and 1 cm; 83 between 1.1 and 2 cm; 115 between 2.1 and 3 cm). One-hundred-eighty-three of them were located in the liver and 36 in other abdominal organs (pancreas, 10, adrenals 9, lymphnodes 9, kidney 5, spleen 3). Biopsies were performed with "free-hand" technique using up-to-date ultrasound equipment. The demonstration of the correct location of the needle tip at the time of sampling was looked for with great care. The sensitivity rate was 93%, with a progressive improvement with the increase of the lesion size (83.3% between 0.6 and 1 cm; 91.1% between 1.1 and 2 cm; 95.4% between 2.1 and 3 cm). The specificity rate was 100%. In 207 cases in which the location of the needle tip was clearly demonstrated, the sensitivity reached 97.3% and the negative predictive value 93%. No noteworthy complications were observed. Ultrasonography is a highly reliable guidance modality also in biopsies performed on small abdominal lesions; if the correct location of the needle tip is clearly shown, even a diagnosis of benignity can be confidently made.