Stool samples of 1488 children suffering from acute diarrhoea were studied for bacterial culture and sensitivity. Shigella culture was positive in 143 (10 per cent) children and 53 hospitalized children could be studied in detail. Thirty-six (68 per cent) children were under 2 years of age and peak prevalence was observed in summer months. Fever and diarrhoea were universal features; 96 per cent had blood and mucus in the stools, but 32 per cent started with watery diarrhoea lasting 1-3 days followed by dysentery. Two cases (4 per cent) had watery diarrhoea. Abdominal pain dehydration, and malnutrition were present in more than two-thirds of the cases. Central nervous systemic (CNS) manifestations, renal failure, respiratory manifestations, and subacute intestinal obstruction were seen in 45, 25, 17, and 5 per cent of cases, respectively. Shigella dysenteriae was the commonest organism grown in 57 per cent, followed by Shigella flexneri in 36 per cent, Shigella boydii in 4 per cent, and Shigella sonnei in 4 per cent cases. In the majority, the organisms were sensitive to neomycin (83 per cent), furazolidine (86 per cent), and cephaloridine (87 per cent), whereas Shigella strains were resistant to tetracycline in 93 per cent, ampicillin in 83 per cent, chloramphenicol in 91 per cent and cotrimoxazole in 66 per cent cases. Proctosigmoidoscopy was useful in defining the nature of mucosal lesion, to collect swabs for culture and biopsy specimen for histopathology. Four (8 per cent) cases had pseudomembrane and in two cases Clostridium difficile could be identified. Eight (15 per cent) cases died and two of them had shigellaemia.(ABSTRACT TRUNCATED AT 250 WORDS)