A double-blind comparison of meglumine iodamide and Renografin 60 (52% meglumine diatrizoate and 8% sodium diatrizoate) for bolus excretory urography was performed. Doses of 0.8 cc/kg. to a maximum of 55 cc were administered to fifty patients, twenty-five receiving each drug.There is a suggestion that iodamide may be superior to diatrizoate in pyelocalyceal opacification while being equal to diatrizoate in parenchymal opacification and in types and severity of side-effects.