A good survival of brucellae in the organism with the development of a stable and prolonged immunity was noted in vaccination of guinea pigs with live brucella vaccine prepared from the Br. abortus strain 19-BA. Local reactions were weak, and no general reactions were observed. In using the jet method of vaccination with the injectors bpi-4 and bi-2 on a limited group of persons (194) the local and general untoward response was weak, but in immunological respect this method proved to be effective when the vaccine was administered in a dose of 2.5 x 10(8) of microbial cells. Jet method can be recommended for express vaccination against brucellosis.