It has been postulated that otosclerosis may produce vertigo by several mechanisms. One mechanism is by causing endolymphatic hydrops. We present six temporal bones in which otosclerosis and endolymphatic hydrops coexist. We consider that there is a spectrum-like interrelationship between these two entities. At one end of the spectrum the relationship is coincidental, while at the other end of the spectrum we consider the massive amount of active otosclerosis to be a causative factor in the development of the endolymphatic hydrops.