Microbiologic studies were carried out in 1981-1985 with a total of 25,561 samples--12,878 were cadavers and viscera, 574 were fetuses, 6,208 were swabs of rectal samples. 844 were feces, 4,096 were washings, 493--feed samples, etc. A number of prophylaxis and control programmes were tested under productional conditions with the use of drugs and vaccinations with a live and a killed autovaccine. Salmonella organisms were isolated as follows: 9.05% from cadavers, 2.5% from fecal samples, 1.35% from rectal swabs, 1.2% from washings from the environment, 0.6% from feed samples--all belonging to 19 serologic types. Greatest importance was shown to have S. cholerae suis, which was epizootically specific for swine, however, the part played by var. america also grew as compared to var. kunzendorf. With the exception of several sporadic cases all other serologic types of Salmonellae were isolated from carriers, rectal and fecal samples, and others. In the event of swine salmonellosis under productional conditions better results were obtained with the use of drugs. Both morbidity and mortality rate dropped twice as low with animals treated with a live vaccine once, and with a killed autovaccine four times. Suggested is a prophylactic and control program, following a definite pattern in dealing with swine salmonellosis in enzootic foci, with the use of complex measures.