During the last six years 30 cases of fibrous ankylosis of the incudostapedial joint have been found. At operation tests of ossicular mobility gave evidence of rigidity of the ankylosed joint in all 30 cases and, therefore, the ossicular chain was preserved. A follow-up proved that this policy gave quite satisfactory results: in 25 cases the airbone gap was less than 25 dB, and in the majority of them it was almost closed. Only in two cases should unsatisfactory hearing results be ascribed to defective functioning of the preserved chain. Thus, preservation of an ossicular chain with fibrous ankylosis of the incudostapedial joint seems to be indicated if the intraoperative tests point to a rigid connection of the incus with the stapes.