"Lockjaw" is a good name for tetanus because it emphasizes the most significant early symptom. The first need is to flood the circulation with antitoxin as soon as possible after the first symptoms have appeared, so that toxin in the blood and lymph which is still accessible to antitoxin is neutralized and any further absorption from the wound prevented. A single large dose (200,000 I.U.) should be given by the intraven. route or, if this amt. is not available, as large a dose as possible. In the case of wounds of a limb 10,000 units may also be injd. into the subcut. tissues round the wound or deeply girdling the limb above the wound. In cases with slight wounds the author doubts the advantage of giving further antitoxin. With severe wounds 50,000 units should be repeated at weekly intervals or before any operation, until reflex spasms have ceased. It is difficult to see what is to be gained by daily repetition of injns., for antitoxin continues to circulate in large amts. for at least 10 days after a big initial dose, and repeated injns. are a worry to the patient and tend to increase spasms. To continue to give antitoxin after the reflex spasms have ceased and only tonic rigidity remains is a sheer waste. Antitoxin is also given in-trathecally and cisternally, usually in combination with intraven. injns., and good results are claimed by some workers, though the evidence is conflicting. In the author''s opinion nothing is gained and much may be lost through the excitation of spasms by such procedures, and they are better avoided, particularly under Service conditions. If antitoxin cannot be given intraven. it should be given intramusc. Before using antitoxin, inquiry should be made as to previous serum therapy and for any history suggesting a tendency to allergy or anaphylaxis, and in cases of doubt desensitization should be carried out. If no contraindications are found the serum may be inj. direct into a vein and need not be diluted or warmed. A soln. of 1 in 1,000 adrenaline should be at hand in case of reactions. The wound should be touched as little as possible for an hour after antitoxin has been given. The aim should then be to convert an anaerobic into an aerobic infection by thorough drainage and removal of necrotic and infected tissue and foreign bodies. Wounds should be irrigated 4-hourly with H2O2 through Carrel''s tubes if for other reasons this is suitable, and dressings should not interfere with free drainage. Early excision of wounds, which was introduced in 1917, seems to have lowered still further the incidence of tetanus. An incubation period of more than 7 days, a period of onset of more than 2 days, the presence of local tetanus, and a slight wound only, are all in favor of recovery. Other things being equal, prognosis is better with wounds of the leg than with those of the head, neck, or arm. In war, intercurrent weakness from the severity of the wound itself, from hemorrhage, and from exhaustion has to be weighed against the beneficial effects of active or passive immunization.