NASA has identified the need to develop lightweight structures to support Lunar Lander and Lunar Habitat programs and for the transfer of relevant technology to the Crew Exploration Vehicle and Crew Launch Vehicle programs. Further, NASA called for revolutionary advances in radiation shielding materials to protect humans from radiation hazards during NASA missions. To address this need, International Scientific Technologies, Inc., in conjunction with the College of William and Mary, developed lightweight, multifunctional polymers incorporating nanoparticles consisting of high atomic-number (Z) elements having large neutron-capture cross sections. The Phase I program proved the effectiveness of these polymeric nanocomposites in shielding against both neutron and X-ray radiation. The feasibility demonstrated in Phase I will be realized in Phase II through a research program having four Technical Objectives, including incorporation of metallic nanoparticle and organometallic additives into polymeric materials, fabrication of various polymeric materials of different geometries, measurement and test of composite materials for radiation shielding effectiveness, as well as thermo-mechanical and electrical properties, and optimization of prototype multifunctional nanocomposites for NASA applications. The polymer nanocomposites in Phase II will provide shielding against galactic cosmic radiation, neutron and electromagnetic radiation in rigid and flexible structure habitants in deep space and lunar missions.