PIP: The role of Campylobacter coli as an etiological agent of diarrhea in children and the pathogen's presence in nondiarrheal children was examined in the region of Chandigarh, India, from May, 1981, to July, 1982. A total of 768 fecal samples from 447 children, 159 symptomatic and 288 asymptomatic, was collected, along with food, water, soil, and animal dung samples from the village. In diarrheal and nondiarrheal groups, C. coli was isolated with frequencies of 3.1% and 3.8% respectively. This difference was not statistically significant. A 4-fold rise in agglutinating antibody titer was observed in a child having diarrhea due to C. coli, suggesting the presence of C. coli infection. Except for 1 sample (fecal material of a fowl) none of the tested animals or environmental sources contained C. coli. The lack of Campylobacter isolation in asymptomatic contacts and family members suggests that there is little person to person infection in the community studied. C. coli has not been reported elsewhere as frequently as in the present study. All strains were found to belong to serotype 49. These strains were typed by the Lior method, and were found to be Lior serotype 35. The study demonstrates that C. Coli infection is prevalent in India, and indicates the specific geographic distribution of C. coli in this part of the country, but the role of C. coli as a diarrheal pathogen requires further study.