As the largest government building in Orange County, the 10-story Ronald Reagan Federal Building uses a dual seismic-resisting system that combines steel braced frames and a steel moment-resisting frame. This system provides a high level of seismic performance and good control of building deflection, in spite of an unusual 20-foot, floor-to-floor height. A landscaped plaza level with both steel and concrete framing transfers forces from the curved tower above to the rectangular grid of the parking levels below. As the engineer of record, we worked with a curtain wall consultant to design a stainless-steel support for the tall glass and stone-veneer curtain wall system, which allows lateral movement during an earthquake.