Abstract: A radiation-shielding material is made of hydrogen-filed glass microspheres embedded within a suitable binder and held within a suitable support structure. The shielding material can be customized to various radiation field environments by adding a metallic coating to the microspheres or adding metal to the binder. In addition, the microspheres can be filled with a combination of gases or supplemented by other microspheres filled with different gases to meet specific radiation shielding requirements.