Patients below 5 yr of age, hospitalised for shigellosis over a period of four years (1984-87), were studied. During the epidemic of bacillary dysentery (1984) isolation of different Shigella spp. as well as Shigella dysenteriae type 1 was high. Decreased isolation of Sh. dysenteriae type 1 and increased isolation of Sh. flexneri was observed during post-epidemic years (1985-87). Isolation of different Shigella spp. was always above 25 per cent from patients with dysentery and greater than 7 per cent from those with watery diarrhoea during the post-epidemic years. Higher incidence of shigellosis was observed amongst older children (greater than 3 yr). Most of the shigellosis patients complained of blood and mucus in stools. Vomiting was common among shigellosis patients presenting with watery diarrhoea whereas fever was commonly seen in patients with both dysentery and watery diarrhoea. Most patients of shigellosis presenting with blood and mucus in stools had no dehydration.