The fabrication of IR optical fibers for the 2- to l4-μm region is described. Both cylindrical and square fibers fabricated from extruded rods and tubes are discussed. The physical proper-ties of the GeSbSe glasses and optical fibers are reviewed. Fab-rication of different fiber bundles is also reported. The applications of IR optical fibers and bundles are described, and system performance and parametric analysis are developed for some applications, including thermal imaging, IR sensors, CO2 laser power guide, and low-loss optical fibers.