Diabetes represents a risk factor for patients undergoing surgery, not only in emergency but also in elective situations. All efforts in such patients are addressed to the restoration of the most physiologic conditions in respect for glucose balance and glucose metabolism since the preoperative phase, and during all the perioperative period. As these patients have to observe a more or less long period of preoperative and perioperative fasting since the day preceding the operation, any oral anti-diabetic regimen has to be timely discontinued, and the use of insulin is necessary. The doses of insulin have to be defined preoperatively with respect of the metabolic needs of the patients in the days preceding the operation, and must be able meanwhile to reduce blood glucose among the physiologic values, in absence on any urinary glucose, to restore a correct metabolism. The simple management form introduced in the paper for this purpose, and in use in our department through many years, makes easier getting and keeping all this aim and is extremely useful not only for the residents but also for the nurse staff. Its main characteristic is to offer daily, and for the single meal, a direct visual comparison of insulin dose and blood glucose level, in respect of a correct and constant caloric alimentation.