Neurologic complications occur frequently in patients with cancer. After routine chemotherapy, these complications are the most common reason for hospitalization of these patients. Brain metastases are the most prevalent complication, affecting 20 to 40 percent of cancer patients and typically presenting as headache, altered mental status or focal weakness. Other common metastatic complications are epidural spinal cord compression and leptomeningeal metastases. Cord compression can be a medical emergency, and the rapid institution of high-dose corticosteroid therapy, radiation therapy or surgical decompression is often necessary to preserve neurologic function. Leptomeningeal metastases should be suspected when a patient presents with neurologic dysfunction in more than one site. Metabolic encephalopathy is the common nonmetastatic cause of altered mental status in cancer patients. Cerebrovascular complications such as stroke or hemorrhage can occur in a variety of tumor-related conditions, including direct invasion, coagulation disorders, chemotherapy side effects and nonbacterial thrombotic endocarditis. Radiation therapy is the most commonly employed palliative measure for metastases. Chemotherapy or surgical removal of tumors is used in selected patients.