Abstract: In a method for the machining of material using a laser with detection of the material to be machined, laser light is directed at the material via a laser optical system and the light re-emitted by the material is guided to a first detector arrangement which measures the intensity of the light and behind which there is connected an evaluation circuit for controlling the laser power or energy. The energy fed to the material via the laser optical system is measured, and the detector arrangement supplies to the evaluation circuit a display signal which indicates the beginning of the dielectric breakdown. The evaluation circuit reduces the power of the laser and/or interrupts the laser pulse if no display signal has as yet occurred at a predetermined time at which a predetermined energy was fed to the material.