Adaptive optics is a technology that can remove the blurring effects of turbulence in the earth’s atmosphere, so that telescopes on the ground can “see” as clearly as if they were in space. I will describe the basic principles of adaptive optics, and illustrate why lasers are needed to increase the fraction of the sky where one can apply adaptive optics corrections. As one example of astronomical observations which have benefitted strongly from adaptive optics correction. I will describe our recent detections of dual supermassive black holes in colliding galaxies. I will conclude with a look forward to the adaptive optics systems of the future.