John Leonard Olson was an American radio personality and television announcer. Olson is perhaps best known for his work as an announcer for game shows, particularly the work he did for Mark Goodson-Bill Todman Productions. Olson was the longtime announcer for the original To Tell the Truth and What's My Line?, and spent over a decade as the announcer for both Match Game and The Price Is Right, working on the latter series at the time of his death.

To Tell the Truth is an American television panel show in which four celebrity panelists are presented with three contestants and must identify which is the "central character" whose unusual occupation or experience has been read aloud by the show's moderator/host. When the panelists question the contestants, the two impostors may lie whereas the "central character" must tell the truth. The setup adds the impostor element to the format of What's My Line? and I've Got a Secret.