This Small Business Innovation Research Phase I project proposes to develop high-power mid-IR CW semiconductor laser diodes. The mid-IR laser diode will be grown via MOCVD on an InP substrate using a novel technique that overcomes the strain limitation on wavelength in the InP system. By making use of the well-developed technology for the growth and fabrication of InP-based lasers, high power, low-threshold and efficient lasers will be obtained in this previously inaccessible wavelength range. The development of mid-IR lasers will have important applications for gas monitoring, LIDAR systems, and Infra-red countermeasures. Growth of these long wavelength lasers by MOCVD will enable large scale production and hence reduce the cost of these devices.