Shigellosis is endemic in Bangladesh and other developing countries. Asymptomatic carriers have been incriminated in the maintenance and spread of the disease in the community. To study the incidence of the asymptomatic carrier state of Shigella, we conducted surveys in two groups of children under 5 years of age. The first group consisted of 249 ill children who did not have diarrhoea, and the second group consisted of 699 apparently healthy children. The Shigella carrier rate in the first group was 6.4% and that in the second group 2.1%. These carriers may be important in maintaining the transmission of Shigella organisms in the community.