Stridor in neonates and infants is a symptom that indicates partial obstruction of the large diameter airways. Its presence should prompt a thorough examination and workup. Steps in evaluating stridor include a careful history and physical examination and rapid assessment of the severity of the clinical situation. Infants with respiratory distress and severe stridor should be safely and urgently transported to a tertiary care center, and colleagues from the departments of otolaryngology and anesthesia-critical care should be alerted. An essential component of the physical examination is auscultation. The phase of respiration in which the stridor is heard best provides important clues to help localize its cause. Radiographs, including plain films, dynamic fluoroscopic airway films, contrast esophagography, CT, and MR imaging are useful in specific clinical situations, based on the likely differential diagnosis. The anatomic causes for stridor in infants and neonates are vast. Successful management depends on expert consultation, proper equipment, and a staff that is experienced in the management of pediatric airway problems. The trend over the past decade has been to significantly decrease morbidity and mortality and also to decrease the number of tracheotomies necessary to stabilize pediatric airways. The best treatment outcomes result when there is good cooperation and communication among pediatricians, otolaryngologists, pulmonologists, and anesthesiologists.