The design and synthesis of several new types of functionalized room-temperature ionic liquids (RTILs), ionic polymers based on RTILs (i.e., poly(RTIL)s), poly(RTIL)-RTIL solid-liquid composites, and gelled RTIL systems for gas separations and reactive vapor transport applications are presented. The design concepts behind these new RTIL materials are discussed in the context of first, CO2 removal from CH4 and N-2 for natural gas purification and greenhouse gas reduction, respectively; and second selective blocking or sorption of chemical warfare agent simulant and toxic industrial compound vapors from water vapor for protection applications. The role of the RTIL components and their unique properties in these two separations areas will be highlighted.