The Impossible Years is a 1968 American comedy film directed by Michael Gordon, and starring David Niven. The film also features Lola Albright, Chad Everett, Ozzie Nelson in his final film appearance, and Cristina Ferrare, who was 17 years old at the time the film was shot. It is based upon the 1965 play of the same name by Bob Fisher and Arthur Marx, the son of Groucho Marx, and was adapted for the screen by George Wells.

The eponymous theme song was written by The Tokens and performed by The Cowsills.