Seismic Isolation to Protect Buildings a fail safe method to protect buildings from earthquakes. If a concrete slab is poured with a very smooth upper surface and coated with a grease of low viscosity, it can serve as the base of a thick reinforced concrete slab, which if made an integral part of a building built above it, will protect that building against sideways forces that are the main source of destruction during an earthquake. This will be especially affective if the upper slab is a large fraction of the total weight of the building. This should be much less expensive than current isolation methods. This is especially so since the upper slab does not have to be smooth on top and can have its weight increased by incorporating boulders, for instance. Furthermore, its efficacy can be further enhanced by sandwiching more than one slab on top of each other before the final slab that is integral with the building is reached. The most efficacious grease would be silicone grease because of its inherent slipperiness and its resistance to temperature change. It has the further advantage of being more practical for retrofitting a building since it could be installed a hundred square feet at a time and by relatively unskilled workers or manufacturers. The top slab will have to have mild restraint from the sides, of course, such as air filled pneumatic pistons, springs, etc. Making the bottom slab slightly concave would be helpful also. Current methods are anchored firmly to the bottom slab or foundation so sidewise sway can only be partially prevented. Those that are completely isolated are complicated and expensive.