The recycling of rare earth elements is one of the great challenges for establishing a green economy. Rare earths play an essential role in a great many high-tech products and processes: electronic display screens, computer monitors, cell phones, rechargeable batteries, high-strength magnets, catalytic converters, fluorescent lamps etc. Recycling these materials not only results in valuable materials for new products; it also helps in reducing mountains of discarded products. The recycling methods discussed include bioleaching, biosorption, siderophores, algae and seaweed. carbon-based nanomaterials, silica, pyrometallurgy, electrochemistry, hydrometallurgy, solvent extraction and the use of various absorbents. The book references 253 original resources with their direct web links for in-depth reading. Keywords: Rare Earths, Bioleaching, Biosorption, Siderophores, Algae, Seaweed. Carbon-based Nanomaterials, Silica, Pyrometallurgy, Electrochemistry, Hydrometallurgy, Solvent Extraction, Absorbents, Ash, Slag, Red Mud, Contaminated Soil.