After many years of experience, in general we prefer the Nd-YAG laser, although the CO2 laser is an advantage in a few specific cases (lipomas, cranial synostosis). While the focused CO2 laser may be used as a cutting instrument in less vascular tissue with little trauma to the surroundings, the Nd-YAG laser produces a homogeneous coagulation with an energy dependent depth effect. Thus, with the Nd-YAG laser residual tumour tissue can be selectively and with a predictable depth effect thermally destroyed. Because of its excellent coagulation property, the use of the Nd-YAG laser is particularly indicated in highly vascular meningeal tumours. The shrinkage of a tumour and its demarcation which is due to the varying absorption properties facilitates the dissection and allows in addition the preservation of normal tissue.