Flexible airway endoscopy has been used in clinical and research investigations of pediatric airway and pulmonary disorders for nearly 25 years. Not only has clinical use of the flexible bronchoscope improved our evaluation and management of a variety of airway and pulmonary diseases in children, but also research investigations using lavage and biopsy specimens obtained with the flexible bronchoscope have contributed extensively to our understanding of lung inflammation and infection. Improvements and new developments in fiberoptic endoscope technology, training of airway endoscopists, preoperative and sedative medications, patient monitoring, and airway endoscopic techniques, as well as adjunctive minimally invasive and noninvasive diagnostic modalities, continue to refine and enhance the pediatric clinical and research applications of flexible airway endoscopy.