Based upon experimental results from numerous Small Business Innovation Research (SBIR) programs for USAF, NASA, NAVY, NSF and USMC, new protective clothing are being developed that provide significant enhancements in thermal storage and comfort using encapsulated phase change material With a paraffinic phase change core and a polymer outer shell whose latent phase change can be designed to occur at a selected temperature, particles of microencapsulated phase material (microPCM) can range from 3–100 microns in diameter and be added to textile fibers, composites, foams, coatings and liquid coolants. Much larger 1–3 mm macroencapsulated phase change material (macroPCM) particles can also be included within clothing to provide significant improvements in breathable thermal cooling under conditions of high humidity. When microPCM particles of 10–50 microns diameter are added to a flexible matrix such as foams, new materials are created that can provide both enhanced thermal storage and insulation within the same thickness. Enhancements of thermal capacitance of textile fibers and foams can reach 10X or 1,000 % compared to unfilled fibers and materials. The resulting clothing can provide greatly enhanced thermal protection in both hot and cold environments with both low bulk and thickness. Firefighters, race drivers, skin divers and snow skiers are discovering significant protective advantages with these new materials. For example, waterproof and breathable arctic gloves have been shown to provide superior protection to commercially-available ski wear that is less susceptible to loss of thermal resistance with localized compression.