Biphasic cuirass ventilation (BCV) is an emerging negative pressure ventilation (NPV) technology. It only requires fitting an external cuirass to the body to generate negative pressure, compared with positive pressure ventilation, which requires intubation or a mask. BCV could assist in spontaneous breathing and support ventilation by enabling negative pressure in the inspiratory phase to actively move the diaphragm downward and positive pressure in the expiratory phase to release air out of the lungs. BCV has been reported to improve lung function, oxygenation, and cardiac output and reduce the risk of barotrauma. The literature reports the device’s application in various pathological conditions and is used in treating acute respiratory failure and neuromuscular disease. In the following chapter, we analyze some case reports to understand the role of BCV in pathological conditions such as pneumonia, pneumothoraces, barotrauma, and air leak syndrome. The current literature supports that BCV helps increase sputum and improve alveolar exchanges, treating hypoxemia and hypercapnia conditions, reducing and resolving dyspnea, and working on respiratory mechanics. BCV can be used to support positive pressure ventilation or as a replacement where positive pressure ventilation is ineffective or may worsen the patient’s clinical condition. It is contraindicated for patients who are deformed or burned such that the cuirass cannot be applied and for patients who have absolute upper airway obstruction.