To create a rational treatment system for Meniere's disease, it is helpful to recall what is known for sure and what is probably true about Meniere's disease, so as to recognise the stages through which the disease passes from beginning to end. Meniere's disease is a complex disorder of the inner ear, characterised by fullness, tinnitus, fluctuant hearing loss and dizzy spells. Meniere's disease is always associated with, and probably caused by endolymphatic hydrops, although all patients with endolymphatic hydrops do not have Meniere's disease. Meniere's disease is almost always associated with, and probably caused by a small, underdeveloped, abnormally-placed, malfunctioning endolymphatic sac. The first stage is entirely cochlear, where endolymphatic hydrops usually begins, with fullness, tinnitus and low-tone, sensorineural hearing loss, and is most amenable to medical treatment. In the second stage, the endolymphatic hydrops is more widespread, involving the vestibular labyrinth as well. There is fluctuant, low-tone sensorineural hearing loss, fullness and tinnitus, together with dizzy spells. In the third stage, the hearing loss is more severe and no longer fluctuates, with poor comprehension, but fullness, tinnitus, and dizzy spells are the chief complaints. In the fourth and final end-stage, the hearing is very bad, at 55 to 60 db, and no longer fluctuates, with very poor comprehension, fullness and tinnitus, but usually no more dizzy spells, although the patient is unsteady, especially in the dark. Most ears in Stage IV have reduced or absent response to rotation test.