The nutritional impact of a water and sanitation intervention in a rural community of Bangladesh, comprising the provision of handpumps, construction of latrines and hygiene education was assessed. During 3 years, the quarterly anthropometric measures of about 200 children aged 12-35 months from the intervention community were compared with those of a similar number of children from a control area. The interventions reduced the incidence of diarrhoea by 25 per cent among the children less than 5 years of age. There was no significant difference in nutritional status, however, between the two groups of children. Moreover, within the intervention area, indicators of water and latrine use were not significantly related to the children's nutritional status. This suggests that either the obtained reduction of diarrhoea was not large enough to have an impact on nutritional status or that diarrhoea is not an important cause of malnutrition in this community.