Campylobacter jejuni and closely related organisms are important bacterial causes of acute diarrheal illness in the United States. Both endemic and epidemic infections have been associated with consuming untreated or improperly treated surface water. The susceptibility of three C. jejuni strains and Escherichia coli ATCC 11229 were compared with standard procedures used to disinfect water. The results suggest that disinfection procedures commonly used for treatment of drinking water to remove coliform bacteria are adequate to eliminate C. jejuni and further correlate with the absence of outbreaks associated with properly treated water.