When the Federal Building required rehabilitation to improve its seismic resistance and sustainability over time, one of the challenges was that it also housed Sacramento’s Main Downtown Sacramento Post Office, which had to remain in continuous service to the public during the project. The four-story plus basement office building was constructed with steel frame; unreinforced masonry; and terracotta, non-bearing exterior walls. Because the structure lacked a seismic resistive system, Miyamoto designed reinforced concrete shear walls to resist lateral load in both directions and tied the unreinforced masonry and terracotta walls to the main building frame. The retrofit was accomplished in unobtrusive phases. The building presently houses staff offices for the State of California, U.S. Post Office and Federal Building.