Stapedectomy and transposition of the incus to form a columella between the malleus and the oval window was done in three monkey and five cat ears. Cat incudes from 2 weeks to 4 months postoperatively and monkey incudes from 3 to 9 months postoperatively showed gradual replacement of the original bone by periosteal bone. The gross structure of the ossicles was retained. Routine sectioning and staining with hematoxylin and eosin were adequate for determining the approximate degree of vitality of the bone. Fixation of the incus occurred in 3 animals out of the 6 that survived 2 months or more. Excellent position was maintained by the incus. Gelfoam and fat were adequate for oval window grafts in this procedure. Transposition of the incus is a feasible technique.