This chapter presents a complete picture of current knowledge on useful and green bio-solvent “terpenes” obtained from aromatic plants and spices through a steam distillation procedure followed by a deterpenation process. Terpenes could be a successful substitute for petroleum solvents, such as dichloromethane, toluene, or hexane, for the extraction of natural products. This chapter provides the necessary theoretical background and some details about extraction using terpenes, the techniques, the mechanism, some applications, and environmental impacts. The main benefits are decreases in extraction times, the amount of energy used, solvents recycled, and CO2 emissions.