Design Seismic coefficient(c) of an area is mainly concerned with designing buildings in quake-susceptible area. Here C=CoxZxE where CO=seismic coefficient, Z= zone factor and Ee Soil structure factor of that area. In designing quake -proof buildings, care should be taken to select the proper site and the design should be against collapse under extreme earthquakes, simple and symmetrical and well-equipped with rescue measures and steel and reinforced concrete should be used. Such light-weight, strong and ductile buildings reduce the damage down to 0.001%.