Hospital admission rates for asthma in the 5 to 14 yr age group are three times higher in Fiji Indians than in Melanesian Fijians. Conversely, admission rates for pneumonia are three times higher for Fijians than Indians. To determine the prevalence of respiratory symptoms, bronchial hyperresponsiveness, and atopy, a questionnaire in three languages was distributed to 2,173 Suva City school children (mean age 9.6 yr), half of whom were sampled for histamine inhalation and skin-prick allergen tests. Prevalence of wheeze in the previous 12 mo was identical in both ethnic groups (20.6%). Productive cough was more common in Fijians (29%) than Indians (17%, p < 0.0001). Bronchial hyperresponsiveness was twice as common in Indians (30%) as Fijians (15%), relative risk 2.1 (95% confidence interval [CI]: 1.5 to 2.8), p < 0.0001. The combination of current wheeze and bronchial hyperresponsiveness was found in nearly three times as many Indian children (11.3%) as Fijians (4.0%), and the mean bronchial dose-response slope to histamine was steeper in Indians than Fijians. Prevalence of atopy was similar in Fijians (36%) and Indians (38%). Wheeze was significantly associated with atopy and a steeper dose-response slope to histamine, but productive cough was not. Indians may have more severe asthma than Fijians due to genetic or environmental factors acting independently of atopy. The higher prevalence of productive cough in Fijians is consistent with a greater burden of respiratory infection, and is associated with domestic crowding.