There is a growing literature reporting traffic exposure impacts on respiratory health in children. Very few studies in the U.S. have used advanced Geographic Information System (GIS) modeling techniques, such as land use regression (LUR), to estimate exposures on a fine spatial scale. LUR models based on intensive neighborhood monitoring of traffic pollution have not been developed for the Los Angeles (LA) Basin in Southern California, one of most polluted regions in the U.S. There is currently a lack of neighborhood-level air pollution measurements for Californian children that live in high traffic density areas and who may be more susceptible to adverse health impacts from air pollution exposure due to economic disadvantage. Thus, the objectives of this research were to: (1) conduct NOx and NO2 monitoring at 200 locations within LA County neighborhoods with varying levels of economic disadvantage and varying exposures to air pollution originating from vehicular sources; (2) to use these monitoring data to help inform LUR models for predicting traffic pollutant exposures (i.e., NOx, NO and NO2); (3) to use geostatistical models to estimate regional background concentrations of O3 and PM2,5; (4) to evaluate associations between exposure to NOx, NO and NO2 and measures of respiratory health and lung function in children in conjunction with the Los Angeles Family and Neighborhood Survey (L.A. FANS) study; and (5) to evaluate whether concentrations of the more regionally distributed background pollutants (O3 and PM2.5) confound or modify the effects of exposure to the more heterogeneously distributed traffic-related pollutants (NOx, NO and NO2).