Hepatobiliary functional scintigraphy (HBFS) using 99m Tc-labeled Diethyl-IDA was tested in 84 patients suffering from various hepatic and bile duct disorders. The investigated pathologies were: gall bladder dysfunction, parital bile duct obstruction, total obstruction, hepatocellular disease, cirrhosis and drug induced cholostastis. The diagnosis accuracy of the method was found to be 95 %, and the method proved to be useful for guiding the clinician in selecting those additional investigation techniques most apt to define the etiology of the pathological condition accurately. In conclusion, the non-invasive character of the technique, its usefulness even in the presence of elevated bilirubin levels and the information yielded by HBFS make it a method of choice to be placed in the beginning of the test series liver or duct patients are submitted to.