The radiologic findings in 123 hospitalized children with viral disease of the respiratory tract due to adenovirus, respiratory syncytial virus, parainfluenza, influenza, measles, or herpes virus were retrospectively reviewed. Bronchial wall thickening, peribronchial shadowing and/or associated perihilar streaking were present in 107 cases. Patchy pulmonary shadowing thought to reflect disease at a sublobular or lobular level was present in 72 cases, while areas of coalescent more homogeneous pulmonary shadowing were present in only 20 cases. In general the pulmonary abnormalities were widespread; on the average, two to three lobes demonstrated abnormal pulmonary findings. Poorly defined small pulmonary nodules, while radiologically unimpressive, were noted in 49 cases. Air trapping was observed in 61 cases. Hilar adenopathy was seen in only four cases and was unimpressive. There was a striking absence of pleural effusion, pneumothorax, pneumatocele, and lung abscess in the patients examined.