SINCE THE introduction of tympanoplastic surgery, a number of varieties of tissue pedicles, autografts, and homografts have been advocated. The original use of postauricular skin has been replaced, in many centers, by other tissues, largely mesodermal in character. It seems timely to call attention to the natural forces for tympanic membrane growth as well as repair. Spontaneous healing of perforations and, indeed, tympanoplasty are phenomena well described in old and in recent papers. It appears that there are at least two mechanisms which play major roles in growth and repair of tympanic membrane: the induction effect of the annulus and the special nature of basement membrane laminae in the middle layer of the tympanic membrane and in the fibrous annulus. These two factors may be responsible for growth and dedifferentiation characteristics of grafts applied to this area. Indeed, it is possible to expedite spontaneous healing by placing a