A systematic search for Campylobacter jejuni in stool cultures from children with acute diarrhoea showed within two months that the organism was present in 3 out of 17 children. Apart from diarrhoea, the symptoms were different in each case: one child had febrile dysentery, another exhibited symptoms resembling appendicitis and the third one had chronic diarrhoea with denutrition. The condition regressed spontaneously in two cases and after erythromycin treatment in one. Phase-contrast microscope examination of fresh stools may rapidly point to the diagnosis. Routine search for Campylobacter jejuni should yield information on the incidence and epidemiology of these infections in France.