In order to achieve further reductions of mortality in newborn infants it will be necessary to observe four principles. Mothers and infants must be followed for infections developing after discharge from the hospital, bacterial cultures must be made from infants or adults who may be acting as carriers, specific bacteriological study must be made on individual cases rather than periodic mass cultures of hospital personnel, and nurseries must be kept up to recognized standards. Among the problems awaiting solution are the cause and cure of the hyaline membrane syndrome, the improvement of criteria for selecting infants likely to require exchange transfusions in cases of hyperbilirubinemia, and the elimination of iatrogenic disease by more diligent precautions against the sideeffects of drugs. Application of routine measures to entire nursery populations must not be substituted for attention to the individual newborn infant.