This article reviews the most common oncologic emergencies encountered by the radiation oncologist, including malignant spinal cord compression, intramedullary spinal cord metastasis, superior vena cava syndrome, and hemoptysis and airway compromise caused by tumor. Important trials evaluating different treatments for these emergencies are reviewed. The role of corticosteroids, proton-pump inhibitors, surgery, chemotherapy, and radiation therapy in the treatment of patients who have oncologic emergencies is discussed, and patient-specific treatment guidelines are suggested.