In THE YEAR 1963 I had the honor to speak before your Second Workshop about this theme. It seemed to me that since that time there have been no new facts to report. Therefore, when my friend George Shambaugh asked me to speak once more about this theme, I wrote him in this sense. But as he insisted, I made up my mind to study personally the medical records of the patients operated upon since then. I must say that, though I could not by this work discover anything really new, I learned from our experiences and our faults some interesting facts. The material became keenly alive to me as I had executed two-thirds of these 62 operations myself. Up to this date, we cannot give precise explanations about the origin and the causes of tympanosclerosis. A survey of the records demonstrates that more than two-thirds of the patients had