In 533 surgical procedures for cholesteatoma, a closed technique was used in 60%, an obliteration technique with Palva flap was used in 35%, and an open technique was used in 5%. The closed technique has been done in stages in the authors' institution since 1973. The obliteration technique was only staged if the mesotympanum was dissected. In some cases, the Palva flap was partially lifted from the bone to check posterior cavities. A closed technique in one stage provided intact tympanic membrane in 97% of cases, but retraction pocket occurred in 25%; ABG was within 20 dB in 68% of ears if the stapes was intact and in 40% if crura were missing. Obliteration technique in one stage (if the mesotympanum was normal) provided intact tympanic membrane in 100% of cases, but one late residual cholesteatoma under the flap eroded the semicircular canal after 5 years. ABG within 20 dB was achieved in 68% of the ears if the stapes was intact and in 40% if crura were missing. Closed technique in two stages with Silastic sheeting achieved intact tympanic membrane in 97% of the ears. Residual cholesteatoma was removed at the second stage in 24% of the ears. ABG within 20 dB was achieved in 57% of the ears if stapes was intact and in 52% if crura were missing. Ten percent of the ears underwent an obliteration transformation at the second stage because of large mesotympanum cholesteatoma or retraction pocket. Late retraction pockets were observed in 10% of cases. Obliteration technique in two stages provided an intact tympanic membrane in 96.8% of the ears.(ABSTRACT TRUNCATED AT 250 WORDS)