Symptoms of migraine and vertigo frequently co-exist. In some circumstances, co-morbidity of these features is unrecognized. Recently there have been criteria developed to define migrainous vertigo, providing a standardized framework for evaluating patients with both migraine and episodic vestibular symptoms. The proposed pilot study is designed to analyze vestibular function in migraineurs with and without co-existing episodic vertigo in order to identify a subgroup of patients in whom vestibular abnormalities exist as part of the pathology of chronic migraine. Identification of unique vestibular features may suggest alternative therapeutic options.