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The HST Servicing Mission, scheduled for December, 1993, should install COSTAR and a GHRS Repair Kit. COSTAR can restore full optical performance to all of HST's axial instruments, and for the GHRS it will make the Small Science Aperture deliver more than twice the throughput it now does, and will make it possible to isolate objects in crowded fields. For the LSA, the COSTAR optics will improve the spectroscopic resolution for point sources observed. The other essential properties of the GHRS (resolving powers, modes of operation, etc.) should remain unchanged except that COSTAR will impair instrumental throughput below about 1200 \AA\ because of the coatings on the COSTAR mirrors. The Repair Kit should make it possible to attempt to revive Side 1 of the GHRS without risk to Side 2 operations, thereby restoring the ability of the GHRS to obtain spectra with the detector that is optimized for far-ultraviolet spectroscopy (from about 1100 to 1700 \AA), both for echelle observations and for low-dispersion spectroscopy of faint sources. The post-Servicing-Mission capabilities of the GHRS will be presented, together with a summary of plans for making those capabilities available to the user community.
