A technique is demonstrated for reducing the rapid intensity fluctuations in the beam of a single frequency, polarized CO
2laser tuned to the

transition at 10.6 μm. The method uses a Stark-tunable absorption line in NH
2D to compensate for the fluctuations of the laser output. Substantial reductions in laser beam intensity noise have been obtained. The method may be applied to other lines of the CO
2laser and indeed to other types of lasers.