Arthur D. Frankel, Research Geophysicist in the Seattle office of the U.S. Geological Survey, was selected as the 2010 Joyner Lecturer. He delivered his lecture at the SSA April 2010 Annual Meeting in Portland, Oregon. Dr. Frankel’s work provides the crucial bridge at the interface of earthquake science and engineering to produce the national seismic hazard maps. Dr. Frankel and his team draw upon a wide body of results from earth science research and earthquake monitoring. These data are used as the definitive basis for the National Seismic Hazard Design Maps. The design maps are in turn used in the seismic safety elements of model building codes adopted by communities in the United States to protect society from earthquakes.