Susan Hough is a seismologist with the Southern California Earthquake Center. She is author of Earthshaking Science: What We Know (and Don’t Know) about Earthquakes (2002) and coauthor with Roger Bilham of After the Earth Quakes: Elastic Rebound on an Urban Planet (2005). Address: U.S.G.S., 525 South Wilson Avenue, Pasadena, CA 91106. Internet: hough@gps.caltech.edu