Chronic needs for higher materials performance in present and future commercial and military systems mandate improvements in materials properties. High melting point, low density and high strength are among the material properties necessary to achieve future system performance goals. Such requirements can no longer be met using conventional metal alloys (including aluminum-based alloys which melt at only 660 C). Magnesium-based intermetallics are among the best candidates to fulfill the aforementioned requirements. Based on density, melting point (926 C), crystal structure (B2), and oxidation resistance considerations, an intermetallic compound MgY has significant potential as a light- weight material for 500 C - 550 C applications. The Phase I investigation concentrates on establishing the room and high temperature mechanical properties of the intermetallic MgY, improving the room temperature ductility, fracture toughness and elevated temperature strength of the intermetallic. The Phase I investigation should establish the potential of dispersion- strengthened MgY for further development under a Phase II program. Unique plasma synthesis processing will be utilized to produce these magnesium intermetallic alloys with specific strengths higher than heretofore reported. High strength-to-weight ratio magnesium intermetallic alloys have a high demand in aerospace and transportation applications. Further, fiber-reinforced composites based on such intermetallic matrices exhibit very high specific properties.