Diabetic papillopathy has been characterized as a syndrome in which predominantly young, insulin-dependent diabetics develop transient edema of the optic disc with minimal impairment of the function of the optic nerves. In this study, four patients with long-standing insulin-dependent diabetes mellitus and acute disc swelling in one or both eyes were evaluated. The most unusual finding in these cases was that three had proliferative retinopathy either at the time the disc edema was discovered or very shortly afterwards. The fourth patient also developed this condition subsequently. It is important to be aware of diabetic papillopathy and to recognize the condition early enough so that the patient may be spared unnecessarily extensive neurological evaluations and invasive procedures. Patients with diabetic papillopathy should be closely observed so that the presence or development of proliferative retinopathy may be established.