GHRS Instrument Science Report 067 "Calibration Product Review for the GHRS in Early Cycle 4" 11/94 Stephen J. Hulbert, Lisa E. Sherbert, David R. Soderblom, and Claus Leitherer Abstract excerpted from the report: The pipeline reduction program, calhrs, determines how to calibrate a particular dataset by checking "switches" that are set to PERFORM or OMIT and by access- ing various calibration reference files. These reference files are summarized in GHRS Calibration Reference Files and Tables, by S.J. Hulbert and L.E. Sherbert, the latest version of which is dated 11 July 1994 and is available on STEIS as a PostScript document. That document is included in this one, with additional explanatory comments. A brief review of the calibration process and control switches is also included here. Additional information on the usage of calhrs and the reference files may be found in HST Data Handbook, issued in February, 1994. This document contains a listing of all GHRS Reference Files and Tables that are presently available in the Calibration Data Base System (CDBS). The tables herein are intended to provide a history of the differences among the files and tables which are used by Post Observational Data Processing System (PODPS) to calibrate GHRS data. This Report provides a description of the files and their usage as of 30 September 1994, for the convienence of Cycle 4 HST users.