~Before the Operation~ the patient must be made ready to take the anesthetic. This is done by preventing an accumulation of food in the intestinal tract. The day before the operation, then, it is necessary to limit the diet materially by giving food in small amounts. The light diets prescribed in acute conditions are as a rule suitable, unless otherwise indicated. ~The Day of the Operation~ a cup of tea, coffee, or broth may usually be given, with a cracker, unless the operation is to be performed early in the morning, in which case the patient is given no food at all. Some physicians allow a glass of milk on the day of the operation, but this is left entirely to the physician in charge. ~After Operation~ a period of total abstinence from both food and water is necessary in order not to increase or induce nausea and vomiting. As soon as these symptoms subside, unless otherwise indicated, a certain amount of hot, cold, or carbonated water may be given. After this, albumen water may form the first nutrient administered. Milk, broth and fruit beverages follow the giving of albumen water, after which the semi-solids, such as soft eggs, gelatin and milk soups, constitute the convalescent diet. ~The Character of the Diet~ after the operation depends wholly upon the nature of the disease for which the operation was deemed necessary. ~Diet After Gastro-enterostomy~ must be adjusted in order not to increase the acid content of the gastric organ, otherwise the delicate mucous linings of the intestines would be subjected to direct contact with materials which are irritating in character, owing to the fact that the mass passes through the new opening and has thus been deprived of the neutralizing agents found in the upper part of the intestinal tract. Under the circumstances milk, albumen water and fine cereal gruels are the best foods from which to formulate the diet after the necessary period of abstinence and fluid diet. ~After Appendicitis~, as a rule, no food is given for five days in cases where there has been a pus formation and the appendix gangrenous. Otherwise the routine treatment diet is given--water, then albumen water, followed by broth, milk and fruit beverages, fine cereal gruels, etc. ~After Liver and Gall bladder Operations~ the character of the food must be considered. The fats are not well handled in such conditions and must be avoided as far as possible. Broths must be well skimmed and the milk fat free. Buttermilk and koumiss are probably the most suitable forms in which to give milk in these cases. ~After Kidney Operations~ the work of elimination through kidney must be limited as far as possible in such cases. While it is impossible to rest the organ entirely, the giving of a proper diet under the circumstances will do much toward relieving the strain placed upon it. The protein foods, with the exception of milk, must be excluded from the diet. The regime practiced in acute nephritis gives the most satisfactory results.