['To determine the association between the high incidence of lower respiratory tract infection (LRI) documented among young Alaskan children and the absence of modern water service (in-home piped water/septic system or water delivered by closed haul truck) found commonly in rural Alaskan communities.', 'A community-level analysis was performed of all 108 Alaskan communities with at least 15 children <2 years of age enrolled in Medicaid during 1998-2003. Community LRI incidence rates were determined from a Medicaid database with standard LRI billing codes. Potentially confounding community-level demographic variables were obtained, as was availability of water service.', 'During linear regression analysis, the percentage of households with modern water service in a community predicted community-level outpatient (beta = -0.53; P < .001) and inpatient (beta = -0.15; P = .088) LRI incidence rates when controlling for the degree of household crowding, unemployment, adult education, tobacco cigarette use, wood stove use, and poverty. Modest improvements in water service delivery were not shown to be associated with changes in LRI burden.'] Is lack of piped water and sewage services associated with pediatric lower respiratory tract infection in Alaska?