Since January 1978 four outbreaks of bovine venereal campylobacteriosis, associated with Campylobacter fetus subspp fetus, have been investigated. The herds demonstrated a variety of presenting signs, and the outbreaks were confirmed by vaginal mucus agglutination tests and isolation of C fetus subspp fetus. A greater recovery of C fetus was achieved by reducing the oxygen tension in the atmosphere used for incubation to a greater extent than usual. Bradford's brucella agar was found to be a suitable selective media for C fetus.