This is an introductory book on seismic design for buildings. Seismic research has progressed substantially since 1975, when this book was published. But the material does not cover complex calculations or code provisions, instead focusing on developing the thought process for overall building design. How do we make our structures safe? Why do we want ductility? What happens in the time surrounding an earthquake? These are all questions that are briefly explored. The book is a short read with effective illustrations and simple definitions for an otherwise complex subject.