instantly recognizable this is his handwriting on the sign of the beverly hills hotel? yeah. reporter: but for many his name is still unknown. paul r. williams, california s first accredited black architect. he is one of the greatest architects that america has produced. reporter: born in los angeles in 1894, williams became the most influential black architect of the 20th century. designing the homes of america s biggest celebrities, from frank sinatra to lucille ball. he was interested in social impact. reporter: often in neighborhoods where he wasn t allowed to own property himself. today just 2% of american architects are black why do you think that is is it barriers to entry, lack of exposure we need to prioritize diversity. who can be in the room to make those power judgments about what gets built, where it gets built. we need to be at the table this is another important area reporter: which is why the university of southern california launched a brand-new progr