The High-Resolution Spectrograph (HRS) covers the 105 nm to 320 nm wavelength range at nominal spectral resolutions 103, 104 and 105. It employs one ruled, plane, first-order grating (600 grooves/mm), four holographic, plane, first-order gratings (3600, 4320, 4960 and 6000 grooves/mm), one r/2 echelle (316 grooves/mm) and two ruled, multi-partite, concave cross dispersers (88 and 198 grooves/mm). These gratings are all replicas. The absolute efficiencies of the first-order gratings were measured by the Goddard Space Flight Center (GSFC) before integration into the HRS. The spectral resolution was derived from line-width measurements in the Pt spectrum during pre-flight calibration of the complete instrument at the Ball Aerospace Systems Division (BASD). Relative scattered-light levels were determined from gaseous absorption spectra. In some of the holographic gratings spurious images were observed parallel to the spectra. In the echelle the effective blaze angle in the UV was derived from relative-efficiency measurements and found to be about 62.8°. The spectral resolution and the scattered-light background were measured by the same techniques as above. Ghosts were detected at 0.45 interorder distances. Their relative intensities are less than 0.1% at 150 nm.