A staple of early 80s sitcoms.
http://www.cnn.com/2017/10/24/entertainment/robert-guillaume-obit/index.html
http://www.cnn.com/2017/10/24/entertainment/robert-guillaume-obit/index.html
And let's not forget where the Benson character originated: Soap.He actually was in a few sitcoms from the '70s. He had a cameo as a doctor in an episode of All In the Family.
They just don't make realistic shows like that anymore.He started out as head of housekeeping and ended up LT Governor. One of my faves.