Obliteration of old mastoids and wet middle ears with autologous abdominal fat seems to be a reliable technique to render chronically discharging mastoid cavities or open middle ears dry and closed. This paper is the third in the series and looks at the intermediate results at five years. Of the 16 patients (one bilateral) 94.1 per cent of the ears are still dry and uninfected with closed external meati. Recurrent cholesteatoma was found in two patients at implantation and removed.