This article summarizes the emergency department approach to diagnosing cerebellar infarction in the patient presenting with vertigo. Vertigo is defined and identification of a vertigo syndrome is discussed. The differentiation of common vertigo syndromes such as benign paroxysmal positional vertigo, Meniere's disease, migrainous vertigo, and vestibular neuritis is summarized. Confirmation of a peripheral vertigo syndrome substantially lowers the likelihood of cerebellar infarction, as do indicators of a peripheral disorder such as an abnormal head impulse test. Approximately 10% of patients with cerebellar infarction present with vertigo and no localizing neurologic deficits. The majority of these may have other signs of central vertigo, specifically direction-changing nystagmus and severe ataxia.