• There is a need for vaccination against tuberculosis in the United States because the number of new cases reported annually remains high despite the dramatic decline in mortality. The safety of BCG vaccine has now been tested by millions of vaccinations in many countries, and the introduction of the multiple puncture method of administering it has practically eliminated all complications after vaccination. The advent of the freeze-dried vaccine has made it possible to standardize completely the viability, potency, and sterility of BCG vaccine as well as to determine its safety before distribution. Recent studies comparing vaccinated with unvaccinated groups of children have been carried out under especially rigorous conditions and leave no doubt that the reduction in the incidence of tuberculosis was due to BCG vaccine. There is reason to believe that this reduction will more than compensate for the decline in usefulness of the tuberculin test for the determination of incidence of infection in localized areas of high prevalence. BCG vaccination has several advantages over chemoprophylaxis. The evidence now available argues strongly for the vaccination of infants and children against tuberculosis in areas of high incidence and for those individuals who will be unavoidably exposed to tuberculosis (medical and nursing students, individuals in tuberculosis households, etc.), with revaccination at suitable intervals in order to maintain as high a level of immunity as possible.