Recent advances in the performance of GaInAsSb/AlGaAsSb quantum‐well diode lasers have been directly related to improvements in the quality of the molecular‐beam epitaxy (MBE)‐grown epitaxial layers. These improvements have been based on careful measurement and control of lattice matching and intentional strain, changes in shutter sequencing at interfaces, and a generally better understanding of the growth of Sb‐based epitaxial materials. By using this improved MBE‐grown material, significantly enhanced performance has been obtained for midinfrared lasers. These lasers, which are capable of ∼2‐μm emission at room temperature, presently exhibit threshold current densities of 143 A/cm2, continuous wave powers of 1.3 W, and diffraction‐limited powers of 120 mW. Such high‐performance midinfrared diode lasers are of interest for a wide variety of applications, including eye‐safe laser radar, remote sensing of atmospheric contaminants and wind turbulence, laser surgery, and pumping of solid‐state laser media.