Infantile enteritis constitutes a major health problem in developing countries. Several investigations into the etiology of this condition among various South African populations have been undertaken during the past few years. Recent studies of black urban infants have revealed that salmonellae, shigellae, enterotoxigenic Enterobacteriaceae, and rotaviruses play a relatively minor role in infantile enteritis. On the other hand, all studies, including a number performed several years ago, have demonstrated that Escherichia coli strains belonging to traditional enteropathogenic serotypes are more frequently recovered from patients with diarrhea than from matched control subjects. These bacteria are particularly prominent during the summer months at the height of the annual gastroenteritis epidemic. Recent studies have indicated the importance of Campylobacter fetus in infantile enteritis, especially in children younger than nine months. The data point to a complex multiple etiology of infantile enteritis in South Africa, which will require clarification before specific preventive measures can be instituted.