The discovery of insulin has opened a new era in the treatment of diabetes. While not supplanting the older method of treatment—that of diet—it has proved itself an invaluable aid in allowing the use of a more liberal diet and in tiding patients over the various crises to which diabetic patients are liable. High on the list of these crises stands any surgical condition that may complicate the disease. Diabetic patients have long been recognized as extremely poor surgical risks, and the mortality, no matter what the surgical condition, has always been high. I believe that insulin, however, will reduce this mortality to a great extent, and the small series of cases here presented would tend to bear out that belief. It is too early in our use of the drug to determine whether or not insulin will reduce the occurrence of certain surgical conditions that are strictly complications of