Abstract: There is provided by this invention a controller for cavity dumping a laser which maintains a consistent output pulse energy level. The constant output pulse energy level is due to the clipping of the circulating power within the laser's cavity upon its reaching a threshold level. In order to further insure that the output pulses are of equal energy even within a laser that is pulse interval modulated, the threshold level for the circulating power within the laser's cavity is adjusted according to a predetermined ratio of the number of times the circulating power is clipped to the number of times the circulating power is not clipped so that the predetermined ratio is maintained.