Retaining walls are used to retain earth in a vertical position where there is an abrupt change in ground level. There are several types of retaining walls including gravity, cantilever, counterfort, and buttress walls. Cantilever walls are the most common type for heights up to 8 meters. They consist of a vertical stem and base slab that behave like one-way cantilevers. Counterfort walls include transverse supports called counterforts to reduce bending moments in the stem and slabs. Proper design of the stem, heel slab, toe slab, and foundation depth is required to resist overturning, sliding, soil pressure, and bending failure.