Infrequent causes of stroke are likely to be encountered by emergency physicians. Infrequent causes of stroke can be recalled using the ABC-IT mnemonic. Of the many infrequent causes, the five conditions more likely to be encountered are sickle cell anemia, migrainous stroke, antiphospholipid antibody syndrome, arterial dissection, and cocaine-related stroke. Consideration of the use of thrombolytic therapy in a patient with stroke from any cause lies at the forefront of treatment strategy in the emergency department.