Clinical and computed tomographic (CT) data on a consecutive series of 41 elderly patients with affective disorders are presented, and comparisons made with a group of 50 healthy controls. In both groups ventricular size increased with age, but only in the controls was there an age correlation with sulcal widening. Using clinical and radiological criteria, the prevalence of cerebrovascular disease in the patient group was 12 per cent. A sub-group of patients with enlarged ventricles emerged, whose first depression began later in life, and who at the time of this study were older and showed more "endogenous" features than the remainder. It is suggested that this provides further evidence that organic cerebral factors may have aetiological significance in some depressions of old age.