Campylobacter jejuni, a gram negative rod, is a common cause of acute bacterial diarrhoea. It is transmitted to humans from domestic animal and poultry reservoirs through contaminated water, milk and food. It affects all age groups but especially the young. The majority of patients have a mild self-limiting diarrhoeal illness which is often preceded by constitutional symptoms. Erythromycin is indicated in those more severely affected. Prevention consists of good hygienic practice in the preparation of food and after contact with animals, animal products and infected individuals