Over a 9-year period all maternity patients were screened by rectal swab for salmonella excretion at the time of delivery. 30,471 mothers were screened and 60 (0.2%) yielded salmonellas, 43 (72%) of whom were symptomless excretors. Seven of the 60 babies (12%) excreted salmonellas, all of which were the same organism as in the mothers. Five had uncomplicated gastroenteritis in the neonatal period, but no mother or child suffered invasive disease and no incidents of hospital cross-infection occurred. These results show that screening is unjustified unless there are problems of cross-infection.