An experiment on guinea pigs immunized with staphylococcal vaccine prepared from water-soluble antigens revealed that the degree of developing sensitization and specific resistance was essentially determined by the method and schedule of the administration of the preparation. The intranasal administration of the vaccine induced a lesser degree of sensitization in comparison with its subcutaneous injection. The optimum response to the administration of the vaccine (a low sensitization level and a high degree of protection from infection) was observed in the animals immunized first intranasally and then by subcutaneous injection. The subcutaneous injection of the preparation in combination with its subsequent intranasal application induced a more pronounced degree of sensitization and a lesser degree of protection from infection.