There is a wide spectrum of severities in patients with pulmonary bleeding with a range from mild haemoptysis to severe bleeding with an acute risk of asphyxiation. For the management of acute pulmonary haemorrhage, it is essential to identify the underlying cause in order to initiate a target-oriented or causal therapy. The most common causes of localized pulmonary bleeding are lung cancer as well as infections, anticoagulant therapy or bronchiectasis. Diffuse alveolar haemorrhage is mostly due to pulmonary vasculitis or connective tissue disease, but may also occur in pulmonary metastasis, congestive heart failure, coagulation disorders and from many other causes. In a case of severe pulmonary bleeding it is essential to secure the airways and ensure sufficient ventilation, i. e. by intubation with a double-lumen endotracheal tube and by appropriate positioning of the patient. Stabilizing haemodynamics is crucial. Simultaneously basic diagnostic measures, i. e. appropriate laboratory tests, chest X‑ray, computed tomography scan of the chest and bronchoscopy, are performed. Localized pulmonary bleeding usually requires local treatment, like bronchoscopic therapy, bronchial artery embolization or surgery. Diffuse alveolar haemorrhage must be treated systemically, i. e. by immunosuppressive therapy in cases of vasculitis or by medical treatment of coagulation disorders. Even with optimal interdisciplinary management the in-hospital mortality of severe pulmonary bleeding remains high. There is a significant risk of recurrent bleeding depending on the cause of haemorrhage. In patients with "cryptogenic" haemoptysis there is an increased rate of lung cancer within the following years and follow-up of these patients is recommended.