A historical account of the work on lasers at MIT Lincoln Laboratory is presented. Highlighted are the efforts that led to the co-invention of the semiconductor laser and the Laboratory\´s later role in establishing the feasibility of GaInAsP/InP semiconductor lasers for use in fiber telecommunications at

m wavelenths. Descriptions of other important developments include tunable lead-salt semiconductor and solid-state lasers for spectroscopy and LIDAR applications, respectively, as well as ultrastable CO
2lasers for coherent infrared radar.