Twelve preterm infants with bronchopulmonary dysplasia underwent bronchoscopy to determine if airway abnormalities were contributing to persistent pulmonary problems. Indications for bronchoscopy were persistent atelectasis, lobar hyperinflation, or both on chest radiograph (11 patients), unexplained respiratory distress (three patients), and aspiration of tissuelike material from a tracheostomy (one patient). Bronchoscopy revealed abnormalities of the trachea, bronchi, or both in all infants, including partial or near total airway occlusion by abnormal growth of tissue (10 patients); tracheomalacia, bronchomalacia, or both (three patients); and inspissated secretions (two patients). Seven infants died during initial hospitalization. Tracheobronchial abnormalities should be considered as a cause of persistent pulmonary problems in infants with bronchopulmonary dysplasia.