All patients were received in an observation ward where they remained until the results of a throat culture for hemolytic streptococci could be reported back to the ward. Cases reported positive or negative were immediately transferred to their respective treatment wards. All patients in the treatment wards were cultured at intervals of one week and cases found positive were transferred from the “clean” treatment wards to a treatment ward for cases carrying hemolytic streptococci. The ward personnel attending patients in the “clean” treatment wards was examined by throat cultures from time to time with the purpose of eliminating S. hemolyticus carriers. Patients segregated in the streptococcus wards remained there, if uncomplicated, throughout their hospital treatment even though subsequent repeated throat cultures showed that the carrier condition had disappeared. Two wards were provided to care for the pneumonia following measles. One received only patients whose throat cultures were negative for hemolytic streptococci; the other, those positive. It is essential that the throat culture on which this differentiation is made be taken as soon as the complication is reported and that transfer be made promptly on receipt of the report of the culture. To facilitate this transfer, cases of pneumonia complicating measles were reported to the laboratory as soon as diagnosed and cultures were taken at once. The case remained in the measles ward during twenty-four hours, isolated as well as possible, awaiting report of culture before transfer. Within the positive ward for measles pneumonias, distinction was made between streptococcus pneumonias and nonstreptococcus pneumonias harboring hemolytic streptococci in their throats. The two classes of cases were treated in separate sections of the ward. Ear complications were seen and treated by medical officers from the otological service. These patients remained in the measles wards while in the acute stage of measles, but later were transferred to the service of otology whenever further surgical treatment became necessary.