Headache and ocular pain often coexist. Examination of patients with eye disease will usually show visual disturbances, injection, or pupil irregularities. Other patients with an apparently normal examination may have ocular pain or symptoms caused by entities ranging from carotid dissection to primary headache disorders, such as migraine. In this clinical article, Dr. Michael Marmura of the Jefferson Headache Center at Thomas Jefferson University focuses on the many causes and treatment of eye-related headache. He discusses the management of ocular emergencies, including acute glaucoma and pituitary apoplexy, and unusual diseases such as Tolosa-Hunt, Behcet disease, and optic neuritis related to West Nile virus infection.