Laboratory stapedotomy and stapedectomy revisions were performed in human temporal bones while pyroelectric wave energy analyzers and ultrasensitive thermocouples measured energy absorption at the stapes footplate and in the vestibule. Analysis of these data shows that the visible lasers (argon and KTP-532) possess ideal optical properties and precision for otosclerosis surgery but conversely have less than ideal tissue characteristics. The CO2 laser possesses ideal tissue characteristics. Recent advances in optical engineering and pulsing the energy have increased the precision of this laser to now provide the accuracy required for delicate microsurgery. Two clinical studies analyze the long-term hearing results and complications in patients who had undergone CO2 laser stapedectomy revision (59 patients) and CO2 laser stapedotomy (153 patients). The advantages that these laser techniques provide over conventional surgery methods are discussed.