THE views expressed in this paper are based on observations made since November 4, 1917, in 263 cases of cancer of the cervix of the uterus or its recurrence where radium was used alone or in conjunction with surgery or X-ray. Cancer of the uterine body, of the vagina, urethra and vulva, treated with radium, are not included. Of these 263 cases, about 20 per cent were my private patients and the remainder in great part from the services of Dr. Gellhorn and myself at the Barnard Free Skin and Cancer Hospital. The character of material, especially that coming to the clinic, was very unpromising. In less than one-quarter of the cases was the disease either operable or border-line. The bulk of the patients showed extension either far out into the parametrium or down the vaginal walls. This, together with the fact that a considerable number had been tinkered with by other doctors before they came to us, must serve to account for the relatively low percentage of permanent cures obtained. Out of a total of 100 cancers of the cervix treated from 1917 to 1920, four and one-half years ago, there are alive and clinically cured at the present time eight patients, making 8 per cent of cures. Taking only the 20 private patients the results are better; we find 4 cures, or 20 per cent. In 11 cases the patients were lost track of, but these were, of course, included among the dead. The radium used in these treatments was usually in the form of radium element (150 mgrs.), but in a certain number emanations were employed, especially in 1917–1918, when we obtained emanations for a time through the generosity of the General Memorial Hospital of New York. Since 1922 we have used in addition deep X-ray, both in private work and at the Barnard Hospital in co-operation with Dr. E. C. Ernst. Total dosage. The dosage given depended not so much upon the size of the lesion as on the general condition of the patient. Early cases were given a maximum dose. In 1918 we made the mistake of giving only 2,200 mgrs. to an early case, where operation was contra-indicated, obtaining what proved to be only a temporary cure. Early cancer of the cervix differs from early cancer of the lip in that the lymphatic extensions are not superficial and accessible but deep and inaccessible to any but a powerful treatment. Hence we must, so to speak, over-treat these patients to be sure that our destructive effect goes well out into the parametrium. The average total dosage I am now employing is from 4,000 to 4,500 mgrs., at least two-thirds of which is beta radiation with needles or bare silver tubes. This would be approximately the same as the 6,500 mgrs. gamma radiation employed by Heymann of Stockholm and others.