Very high quality GaxIn1-xAsyP1-y (0 < x < 0.47, 0 < y < 1) lattice matched to InP heterojunctions, quantum-wells, and superlattices has been grown by the low pressure metal-organic chemical vapor deposition growth technique. High quality GaInAsP-InP double heterojunction lasers emitting at 1.3 μm and 1.55 μm have been fabricated with threshold current density as low as 430 A/cm2 and 500 Å/cm2, respectively, for a cavity length of 400 μm. Room temperature CW threshold current as low as 6 mA, 8 mA and 12 mA have been measured (for stripe buried devices with cavity length of 300 μm and stripe width of 1 μm) for 1.3 μm, 1.5 μm and 1.55 μm DEB laser, respectively. Phase-locked high power laser arrays of GaInAsP-InP emitting at 1.3 μm have been fabricated with material grown by two step low pressure metalorganic chemical vapor deposition.