A disease of unknown origin - this is the challenge presented by Ménière's disease and taken up by top clinicians and scientists, members and coworkers of The Vestibular Disorder Research Committee organized by The Ministry of Health and Welfare, Japan. They explore the pathophysiology, diagnosis and treatment of Ménière's disease to help physicians faced with treating this intractable ailment. Specialists investigating the etiology of the disease will welcome these reports which clear the picture for future research.