Much progress has been made in identifying behavioural factors that play an important role in the aetiology of diarrhoea. This short report represents results from a 1-year prospective community-based study of the aetiology of diarrhoea. It was designed to investigate, among other things, mothers' perceptions of the importance of babies' faeces and other factors in the aetiology of diarrhoea. Children whose mothers did not perceive babies' faeces to be important in causing diarrhoea had a 7.4 times greater risk of getting diarrhoea than those whose mothers recognized the relationship. The risk for contaminated food was 6.8 times greater for those children whose mothers did not recognize its importance. For the rest of the factors, there was no meaningful association. Health education should emphasize the polluting nature of babies' faeces and the need for hand-washing when there has been any contact.