Say When!! is an American game show emceed by Art James which aired on NBC television from January 2, 1961 to March 26, 1965. The show was a Mark Goodson-Bill Todman production and James' only game show for them. Wayne Howell was the announcer, and Ruth Halsey was a model. Carmen Mastren was the show's musical director, with the main theme and prize cues played live on two electric guitars.

The series aired live in black and white from NBC Studio 6A at 30 Rockefeller Plaza, New York.