Ralph D. Anderson was an American architect from Seattle, Washington. He was a founder of Ralph Anderson and Partners, later Anderson Koch Smith. Although much of his work is modernist, he is also strongly associated with preservationism. He was an early and significant contributor to the restoration of Seattle's Pioneer Square neighborhood, and also participated in restoration projects along First Avenue in the Pike Place Market Historical District in the 1970s.

The Union Trust Building is a commercial building in Seattle, Washington, United States. Located in the city's Pioneer Square neighborhood, on the corner of Main Street and Occidental Way South, it was one of the first rehabilitated buildings in the neighborhood, which is now officially a historic district. In the 1960s, when Pioneer Square was better known as "Skid Road", architect Ralph Anderson purchased the building from investor Sam Israel for $50,000 and set about remodeling it, a project that set a pattern for the next several decades of development in the neighborhood. Anderson also rehabilitated the adjacent Union Trust Annex.