THE MAIN OBJECTIVE OF THIS PROPOSAL IS TO ADVANCE THE COMPOSITIONAL STUDIES OF VOLATILES (ICES) RELEASED FROM THE NUCLEI OF ACTIVE COMETS. USING HIGH-RESOLUTION INFRARED (IR) SPECTROSCOPY WE PROPOSE FRONTIER MEASUREMENTS WITH FUNDAMENTAL IMPORTANCE FOR UNDERSTANDING INNER COMA PHYSICS THE SOURCES OF VOLATILE RELEASE AND THE MOLECULAR INVENTORY OF COMET NUCLEI WHICH ARE PRIMITIVE (THROUGH NOT PRISTINE) REMNANTS FROM THE EARLY SOLAR SYSTEM. AS SUCH THESE MEASUREMENTS ARE ALSO DESIGNED TO TEST THE DEGREE TO WHICH FORMATION CONDITIONS AND EVOLUTIONARY PROCESSING AFFECT THE CURRENT CHEMISTRY OF COMETS. WE PLAN A COMPREHENSIVE MULTI-MOLECULE INVESTIGATION OF EMISSIONS FROM H2O CH4 C2H2 C2H6 HCN NH3 CO OCS H2CO AND CH3OH IN COMETS. WE WILL UTILIZE STATE-OF-THE-ART GROUND-BASED FACILITIES FOR NEAR-IR ASTRONOMY INCLUDING THE W. M. KECK OBSERVATORY THE NASA INFRARED TELESCOPE FACILITY (IRTF) THE SUBARU TELESCOPE AND THE ESO S VERY LARGE TELESCOPE (VLT). THE PROPOSAL TEAM HAS THE HIGHEST LEVEL OF EXPERTISE WITH DATA FROM ALL THESE FACILITIES. ALTHOUGH WE WILL STUDY BOTH OORT CLOUD COMETS (OCCS) AND JUPITER-FAMILY COMETS (JFCS) 2017 2019 IS THE MOST FAVORABLE OPPORTUNITY TO OBTAIN OBSERVATIONS OF JFCS FOR MANY YEARS TO COME.