Nabih Youssef, a leading California-based structural engineer and seismic design expert who was a pioneering advocate for the use of steel plate shear walls in areas of high seismic risk, died on July 12. He was 80. 

As the founder, chairman and CEO of his eponymous firm Nabih Youssef & Associates, he was a revered expert in development of earthquake engineering codes and standards. The firm's work on the 52-story LA Live project, which used an innovative steel shear wall system, was cited in 2010 for special achievement by the American Institute of Steel Construction. Its incorporation of base isolation in the construction of Our Lady of the Angels Cathedral in Los Angeles after a previous structure was damaged beyond repair in an earthquake earned Youssef and the company recognition from ENR in 2006, as Top Seismic Project of the 20th Century.