'Misfit' is a science fiction short story by American writer Robert A. Heinlein.
It was originally titled 'Cosmic Construction Corps' before being renamed by the editor John W. Campbell and published in the November 1939 issue of Astounding Science Fiction. 'Misfit' was Heinlein's second published story. One of the earliest of Heinlein's Future History stories, it was later included in the collections Revolt in 2100 and The Past Through Tomorrow.