A retrospective analysis of 38 patients clinically suspected of having hydatid disease of the liver has been presented. The space occupying lesion (SOL) was detected in 27 patients on scan, thus confirming the clinical suspicion in 71 per cent of the cases. The success rate of scan in detecting SOL was found to be 100 per cent in contrast to a true positivity rate of 73 per cent for Casoni's test and 71.4 per cent for hydatid serology. The SOL was solitary in 76 per cent and multiple in 24 per cent of the operated cases. It was less than 10 cm in size in 29 per cent and more than 10 cm in 71 per cent of cases. More patients with lesions larger than 10 cm. were operated on than those less than 10 cm., thus giving a shift towads the former in operated patients. The incidence of the lesion in the right lobe alone was maximum (59 per cent) followed by both lobes (35 per cent) and only the left lobe (6 per cent). The sensitivity of liver scan is maximum and when combined with clinical data and immunological tests, the best specificity is also obtained.