Refractory metal alloys based on Mo, W, Re, Ta, and Nb (Cb) find applications in a wide range of aerospace applications because of their high melting points and high-temperature strength. In this paper, we present recent progress in the understanding and applications of these alloys. Recent studies to improve the oxidation and mechanical behavior of refractory metal alloys, and particularly Nb alloys, will also be discussed. Some Re structures, for extremely high temperature applications (> 2000°C), made by CVD and P/M processes, are also illustrated. Interesting work on the development of new W alloys (W-HfC-X) and the characterization of some commercial refractory metals, e.g., K-doped W, TZM, and Nb-l%Zr, continues. Finally, recent developments in high temperature composites reinforced with refractory metal filaments, and refractory metal-based intermetallics, e.g., Nb3A1, Nb2Be17, and MoSi2, are briefly described.