Vibrionic abortion was diagnosed in sheep on 48 occasions between 1963-65 and 3 of these were associated with other major abortion pathogens. The outbreaks were scattered throughout the agricultural area of Western Australia. Time-of-death of 91 infected lambs was: ante-parturient death 50.5%, parturient death 13.2% and post-parturient death 36.3% (deaths occurring immediately after death 28.6%, deaths delayed after death 2.2%, and late post-parturient death 5.5%). The majority of lambs had gross lesions, mainly subcutaneous oedema and excess fluid and fibrin in the serous cavities. The characteristic gross liver foci were present in 37.4% of the infected lambs examined. Seven lambs with signs of starvation had liver lesions: necrotic foci (6) and hepatomegaly (1); Campylobacter fetus subsp. intestinalis was recovered from the liver and/or gall bladder of each of the lambs. Epizootiological observations were reported including outbreaks under hot semi-arid conditions.