A prospective study of the accuracy of computed tomography (CT) and ultrasound was undertaken in 112 consecutive patients with suspected adrenal disease. CT had a sensitivity of 84% (47/56), a specificity of 98% (55/56), and an accuracy of 90%. Ultrasound had a sensitivity of 79% (22/28), a specificity of 61% (14/23), and an overall accuracy of 70%. When patients with Cushing disease and adrenal hyperplasia were excluded, and only masses such as pheochromocytoma, adenoma, and carcinoma were considered, the sensitivity of both CT and ultrasound was increased. Receiver operating characteristic (ROC) curves differed for CT and ultrasound, and strongly supported the diagnostic superiority of CT.