The technology development goal for the Heatshield for Extreme Entry Environment Technology (HEEET) project were to establish a replacement thermal protection system for heritage carbon-phenolic. The investment satisfies the Agency’s need to have a heatshield system capable of handling high enthalpy atmospheric entry missions through a commercially sustainable process. The technology is a dual-layer, tiled-ablator system that takes advantage of advanced three-dimensional textile weaving methods in industry. Ground-based thermal performance tests and experiments demonstrate the thermal protection system will successfully handle a heat flux of 5 kW/cm2 at pressure conditions as high as 5 atmospheres. The development effort includes specifications for textile and material processing standards, ablator tile machining and seaming, property database and response models, analysis tools and design data. The HEEET project successfully advanced a new thermal protection system technology to a technology readiness level of 6, and it is now ready to enable science missions to Venus, Saturn, Uranus and Neptune.