This randomized clinical trial was to compare the effectiveness of prednisone 2mg/kg/day for 3 days vs. dexamethasone 0.6mg/kg for 1 day for treatment of children with mild or moderate croup. It was conducted in a practice-based research network of community pediatricians in the St. Louis area. Outcomes included additional health care for croup, duration of symptoms, nights of disturbed sleep, parental stress, missed work days, and adverse events. Our hypothesis was that community-based treatment of children with mild or moderate croup with multiple doses of prednisone is superior to a single dose of dexamethasone.