Waylon J. Smithers, Jr. is a fictional character voiced by Harry Shearer on The Simpsons. He is the self-proclaimed best friend and personal assistant of Mr. Burns and serves as assistant administrator at the Springfield Nuclear Power Plant. He is usually referred to as Smithers.

A joke central to this character is that he is obviously gay, but closeted. He is also a very strong member of the Springfield's Republican Party. He has been seen campaigning for Mr. Burns for Governor against incumbent Mary Bailey. He also has campaigned for Sideshow Bob for Mayor against Diamond Joe Quimby a.k.a. Mayor Quimby in "Sideshow Bob Roberts"; he tipped Bart and Lisa Simpson that Bob did not win fairly, as “Sideshow Bob’s ultraconservative views conflict with [his] choice of lifestyle.”

Smithers is divorced and lives in an apartment (numbered 19 in the episode "Lisa vs. Malibu Stacy") with a Yorkshire terrier named Hercules. He is an alumnus of the Alpha Tau fraternity. His father, Waylon Sr, worked for Burns until he died saving Springfield from a potential nuclear meltdown ("The Blunder Years").

Early in the series there was much speculation about Smithers' sexual orientation. Eventually revealed as gay, he is still officially in the closet. Smithers' father, Waylon Smithers Sr., was assistant to Mr. Burns at the nuclear power plant. Burns told young Smithers that his father was killed by a tribe of Amazonian women — which is implied to explain his homosexuality. In reality, his father died a hero, sacrificing himself to save the city from a nuclear accident.