NEXT-GENERATION SATELLITE AND SUBORBITAL COSMIC MICROWAVE BACKGROUND (CMB) MISSIONS TARGET THE DETECTION OF GRAVITATIONAL WAVES FROM INFLATION THROUGH THE NANOKELVIN FLUCTUATIONS THEY INDUCE IN THE B-MODE POLARIZATION. WE ALREADY KNOW THAT THIS SIGNAL IS FAINTER THAN THE POLARIZED EMISSION FROM RELATIVISTIC ELECTRONS AND DUST IN OUR GALAXY AT ALL FREQUENCIES EVEN IN THE CLEANEST REGIONS OF THE SKY. THE SUCCESS OF FUTURE CMB MISSIONS THEREFORE DEPENDS ON OUR ABILITY TO CONTROL GALACTIC FOREGROUND CONTAMINATION TO EXQUISITE PRECISION. THIS IN TURN REQUIRES DETAILED OPTIMIZATION OF THE INSTRUMENT DESIGN AND OBSERVING STRATEGY AND VALIDATION AND VERIFICATION OF THE ANALYSIS PIPELINE BOTH IN THE PRESENCE OF SUCH SIGNALS. OUR WORK WILL DELIVER THE SYNTHETIC DATASETS REQUIRED TO DO THIS INCLUDING BOTH REALISTIC MODELS OF THE GALACTIC FOREGROUNDS AND DETAILED MODELING OF THE INEVITABLE SYSTEMATIC EFFECTS INDUCED BY IMPERFECT INSTRUMENTS UNCERTAIN OBSERVATIONS AND APPROXIMATE ANALYSIS ALGORITHMS. IN ADDITION IT WILL SUPPORT STUDIES OF THE COMPLEMENTARITY BETWEEN SATELLITE AND SUBORBITAL CMB MISSIONS THE CROSSCORRELATION OF CMB AND OTHER MISSIONS AND OF THE USE OF THE ALL-SKY MAPS OF POLARIZED MICROWAVE EMISSION PRODUCED BY SUCH A CMB MISSION FOR GALACTIC SCIENCE. TO ACHIEVE THESE GOALS WE WILL COUPLE THE THEORETICAL EXPERTISE ACROSS OUR 4 NODES WITH STATE-OF-THE-ART HIGH-PERFORMANCE COMPUTING (HPC) RESOURCES BOTH (I) TO DEVELOP MORE REALISTIC MODELS OF POLARIZED GALACTIC EMISSION OVER THE FULL RANGE OF FREQUENCIES AND ANGULAR SCALES RELEVANT TO CMB MISSIONS AND (II) TO GENERATE AND REDUCE MORE DETAILED SYNTHETIC CMB MISSION DATA INCLUDING THE CRITICAL SYSTEMATIC EFFECTS.