Summary: The microgravity environment (10-6 g) of space provides a unique opportunity to further our understanding of various materials phenomena involving the molten, fluidic, and gaseous states by reducing or eliminating buoyancy-driven convection effects. The space environment also permits containerless processing, thus eliminating impurities and stresses introduced by contact with container walls. The anticipated scientific results of microgravity materials-science research range from establishing baselines for fundamental materials processes to generating results of more direct commercial significance. The specific objectives include: advancing our knowledge base for all classes of materials, designing and facilitating the executive of microgravity xperiments that will help achieve this goal, determining road maps for future microgravity studies, contributing to NASA's Human Exploration and Development of Space enterprise, and contributing to the national economy by developing enabling technologies of value to the U.S. private sector.