1. 1. In the management of contaminated wounds and potentially contaminated wounds a mixture of equal parts of sulfanilamide and sulfathiazole powder or crystals is applied in generous amounts to every pocket and crevice of the wound at the earliest possible moment whether on the field of battle, at first aid stations, or in the emergency rooms of our hospitals. At the first dressing or at the first inspection of the wound, every effort should be made to get the drug in contact with all raw surfaces. The earlier the drug can be applied after bacterial contamination, the more effective will be the inhibition of bacterial growth. 2. 2. The local application of the drug should be repeated again at operation when a débridement or excision is performed. When operating in a dirty or potentially contaminated wound as during a débridement, or in the closure of a colostomy, the drug mixture should be applied at successive stages as the operation proceeds and as freshly incised areas are exposed in the operative field, endeavoring to impregnate these raw areas simultaneously with or even before their contamination by bacterial organisms. 3. 3. In open resections of any part of the intestinal canal, or in lobectomy or pneumonectomy, the raw surfaces of incised tissues should be impregnated with the drugs before opening the unsterile or infected viscus or bronchus. 4. 4. In localized or general peritonitis, the drug should be brought into contact with all contaminated surfaces. Mixed with blood and tissue fluids, the drug is thinly smeared or rubbed over all infected peritoneal surfaces, thus insuring maximum absorption and least interference with healing. Dumping large masses of the dry powder into a wound is inviting poor healing, as it may then act as a foreign body. 5. 5. “Frosting” a wound reaches only the superficial surfaces of a wound. A suspension of the powder in tissue fluids permits more effective contact with all nooks and crannies, all crevices of a wound. 6. 6. After operation, when vomiting or gastric suction prevent their oral administration, the drugs may be administered subcutaneously, intravenously, or rectally: As a 0.8 per cent solution (8 Gm. in 1,000 cc. Ringer's or normal saline solution) sulfanilamide may be administered by hypodermoclysis. Five Gm. of sodium sulfathiazole dissolved in 100 cc. of distilled water may be given intravenously twice daily. Sulfanilamide may be given intravenously every six hours as a 1 per cent solution (1.5 Gm. in 150 cc. normal saline solution). Four to 6 Gm. of sulfanilamide powder suspended in 100 cc. of tap water may be administered per rectum as a retention enema every six to eight hours for twenty-four hours, and then twice daily. 7. 7. Orally, 4 to 6 Gm. of the sulfonamides may be given as the initial dose, and 1 Gm. every four hours thereafter. Rarely should it be continued in this dosage more than five days, and very rarely after ten days. Marked cyanosis, a scarletiniform rash, or a high unexplained fever demand the discontinuance of the drug. A daily urinary output of at least 1,000 cc. is imperative and 1,500 cc. is preferable. 8. 8. Many cases including compound injuries of the extremities, skull, thorax and abdomen, have been treated successfully according to the above principles. The complete recovery of a case of generalized peritonitis with large collections of pus in the pelvis, in both flanks, and under both leaves of the diaphragm, following the rupture of a duodenal ulcer twenty-seven hours previous to operation, is presented in detail. In this instance, the concentration of the sulfonamides in the blood reached 29 mg. per cent in the course of the first twenty-four hours after operation.