DURING the observation of patients in whom diabetes exists for a period of 20 or more years, certain vascular or degenerative complications appear frequently. Today, attention is concentrated on the specific effects upon the venules and capillaries as well as arterioles, especially in the retinae and in the glomeruli of the kidneys. A common chemical pathology may be discovered to explain these lesions as well as the frequency of atherosclerosis. In patients whose diabetes began early in life, a triad is being recognized with increasing frequency; namely, the sequence in the same patient of neuropathy, retinopathy, and nephropathy. The series of 25 such cases described by Root and Kenney * has been increased to 155 in the present report. DEFINITION The term "triopathy" has been applied to diabetic patients who usually have shown, first, clinical evidence of neuropathy; then, diabetic retinitis, and, finally, the nephropathy of diabetes. In this series, the