SUMMARYTo study the morphology of the adrenal glands of patients with Addison's disease an ultrasound and a computed tomographic scan of the adrenal glands were performed in 28 patients with Addison's disease. Thirteen patients had bilateral, asymmetric adrenal enlargement. In six of these patients, areas of necrosis and calcification were also seen. Six patients had atrophic glands with calcification and nine patients had normal/atrophic glands without calcification. After instituting appropriate treatment, computed tomography (CT) was repeated between 6 months and 3 years later in 10 of the 13 patients with adrenal enlargement. A reduction in gland size was noted in all patients and one had functional recovery. We conclude that the appearance of the adrenal glands on CT depends not only on the nature of the underlying disease but also on the duration of the illness and the type of treatment.