Abstract: A multibeam laser amplifier system is disclosed wherein a plurality of laser beams may be amplified to high power with high efficiency. The beams may then be directed upon a target such as a nuclear fusion fuel element, as in a laser fusion reactor. The system is made up of an array of dual, active mirror laser amplifier units. The laser beams are reflected between successively disposed ones of these units. The units are optically pumped by flash lamps which are arranged in close proximity to the reflective sides of the laser bodies in each unit.