There is little evidence that airway clearance techniques play any significant role in the management of children with an acute respiratory problem or, chronically, in the outpatient setting for any condition other than bronchiectasis. Airway clearance techniques appear to be safe and somewhat effective for children with stable bronchiectasis and suppurative chronic bronchitis (such as cystic fibrosis) and may account for improvements in sputum expectoration, selected measures of lung function, symptoms, and health-related qualities of life. Common strategies for maintaining a clear airway in patients who have chronically impaired clearance of pulmonary secretions include 1) chest percussion alone; 2) chest percussion combined with proper positioning and postural drainage; 3) augmentation of the patient’s own cough; 4) manually-assisted coughing, active cycle of breathing technique, forced expiratory technique, and autogenic drainage; and 5) positive pressure therapy with the use of Flutter valves®, positive expiratory pressure therapy, intermittent positive pressure breathing, intrapulmonary percussive ventilation, high-frequency chest wall compression, and even continuous positive airway pressure. In both Cochrane and Hayes reviews, chest physical therapy techniques did not appear to reduce the overall severity of disease for bronchiectasis but there may be reduction in the rate of progression of disease and improvement in the health-related qualities of life noted above. There may be some advantages to certain techniques and devices in neuromuscular disease with impaired ability to expectorate airway secretions, both acutely and chronically. Physicians should not routinely prescribe airway clearance techniques in previously healthy children with acute bronchiolitis, pneumonia, or an exacerbation of asthma.