Abnormalities on chest film (CXR) have been reported in over half the children admitted for asthma in some series. Many of these abnormalities are only hyperaeration or emphysematous changes. To assess whether significant abnormalities could be predicted by history or on physical examination, the authors studied 129 children admitted for asthma during a 51/2-month period. Prior to examination by CXR the evaluating physician was asked to predict whether pneumonia, pneumothorax, pneumomediastinum, or other significant finding would be present based on the initial evaluation. The films were then reviewed by a radiologist unaware of the physical findings. Causes of the exacerbation were attributed to respiratory infection (74.4%), exposure to a known allergen (10.2%), or noncompliance or error in medication (3.8%). No precipitating factor could be found in 11.6%. CXR findings were normal in 35.7% and consistent with hyperaeration in 35.7%. An additional 22.5% had segmental or subsegmental atelectasis. Pneumonia, possible pneumonia, or pneumomediastinum was seen in only seven (5.5%). There was very poor correlation between the physical examination and roentgenographic findings. The treatment plan was altered in only three cases by the findings on CXR. The authors conclude that clinical presentation is a poor predictor of CXR abnormalities in asthma. Chest film may not be necessary on all admissions for asthma. However, it is recommended that a CXR be obtained on any child who appears particularly ill or who does not respond to therapy as quickly as expected.