Chest wall oscillation refers to the use of external vibrations to help clear secretions from the airways in individuals with respiratory conditions such as cystic fibrosis or bronchiectasis. This therapy is often delivered through a device that attaches to the chest wall and delivers high-frequency vibrations while the person performs breathing exercises. The oscillations help to loosen and mobilize mucus in the airways, making it easier to cough up and clear from the lungs. Chest wall oscillation can be an effective adjunctive therapy to improve lung function and reduce respiratory symptoms in certain patient populations.