Stabilization using light weight fills is described in this chapter. With the lightweight fills, because of their lightness in weight, they will exert little stress to the in situ soil. An example of a very lightweight material is polystyrene. In the form of blocks, also known as expanded polystyrene or EPS, it can be used to cope with the extreme soils, such as very soft clays and peat. Ultra-Lightweight (Bamboo Culm-Recycled plastic block, RPB) Foundation has also been discussed. A design example has been included for the benefit of the reader. Other light weight materials such as scrap tyres, foamed cement paste, and rice husk ash are also discussed.