The pursuit of higher efficiency and cost-effectiveness in Concentrating Solar Power (CSP) systems necessitates the development of advanced heat transfer fluids (HTFs) and materials capable of operating at elevated temperatures. This chapter delves into the latest advancements in HTFs, including high-temperature molten salts, liquid metals, supercritical carbon dioxide, and nanofluids, evaluating their thermophysical properties, thermal stability, and compatibility with CSP technologies. Concurrently, it examines innovative materials for receivers and containment structures, such as high-entropy alloys and ultra-high-temperature ceramics, focusing on their mechanical strength, corrosion resistance, and thermal performance. The integration of these advanced fluids and materials with thermal energy storage systems is also explored, highlighting their role in enhancing the dispatchability and efficiency of CSP plants. By addressing the challenges and opportunities associated with these cutting-edge developments, the chapter provides insights into the future directions of high-temperature solar-thermal systems, contributing to the broader goal of sustainable and efficient solar energy utilization.