Some times lungs get affected with diseases like Chronic Obstructive Pulmonary Disease (COPD- related to smoking, bronchial asthma , air pollution etc.), interstitial fibrosis, Primary pulmonary hypertension. This results in the failure of lungs to allow transportation of gases-oxygen and carbondioxide through it. With this patient goes into respiratory failure –becomes breathless and often requires oxygen even at rest. Such peopled will not live long and their quality of life is poor. In such cases, one or two lungs can be replaced by good lungs from a brain dead donor. 10yr survival after lung transplantation is around 40%. They need to take immunosuppressant drugs life long.