It is but a short step from antiseptic operations to our own era of aseptic surgery, and that a step in the direction of simplicity. Now we know that the sterilization of the air is rarely necessary and have dispensed with Lister's elaborate apparatus. Furthermore, and of far greater moment, experience has taught that the destruction of bacteria before they have opportunity to come in contact with the wound is more effective than efforts to kill them as they approach or after they have invaded the tissues. Initial freedom from bacteria is the ideal of asepsis; to secure it, the modern surgeon is ever watchful of the cleanliness of his hands, his instruments, his dressings, and of the site of operation or whatever may come near it. The importance of the changes wrought by the adoption of aseptic methods requires no emphasis, for the marvels of modern surgery are even more impressive to laymen than to the medical profession. Everybody now understands that strict cleanliness is indispensable to the success of a surgical operation. But the general public has not fully awakened to the same profound necessity in connection with childbirth, although it was child-bed fever that called forth the observations and experiments upon which modern surgical technique rests. Although most obstetrical patients appreciate the fact that there is an advantage in sterilized dressings and sanitary surroundings, few realize the risk they run without them. One must know the mournful history of the past to be adequately impressed with that danger, for we no longer see the epidemics of childbed fever which formerly swept over communities, sacrificing ten of every hundred women as they became mothers. Precaution is no less necessary on that account; the scourge would be rampant again if the reins were loosened. Most instances of puerperal infection are, it is true, referable to lack of care. Nevertheless, the complication develops now and then where all precautions have been conscientiously observed. Under such conditions the infection will in all likelihood be a mild one, and a tedious convalescence usually proves its most disagreeable feature. Such stringent preventive measures as are now practiced in many hospitals have reduced the frequency of infections to the point where only one fatal case, or even less, occurs in a thousand deliveries. These rare cases remind us that vigilance must never be relaxed, and that patients who are confined at home require just as much care as those in hospitals, where conditions are the best to prevent infection and the complications, which follow.