The Fog of War (Eleven Lessons from the Life of Robert S. McNamara) is a 2003 Academy Award winning documentary film about the life and times of former U.S. Secretary of Defense McNamara, illustrating his observations on the nature of modern warfare.

The film was directed by Errol Morris and the original score by Philip Glass. The title is a reference to the phrase "Fog of War", a military concept of battlefield uncertainty during the fighting.

It won the Academy Award for Best Documentary Feature and the Independent Spirit Award for Best Documentary Feature (Screened out of competition at the 2003 Cannes Film Festival.)