Lad: A Dog is a 1919 American novel written by Albert Payson Terhune and published by E. P. Dutton. Composed of twelve short stories first published in magazines, the novel is based on the life of Terhune's real-life rough collie, Lad. Born in 1902, the real-life Lad was an unregistered collie of unknown lineage originally owned by Terhune's father. Lad's death in 1918 was mourned by many of the story's fans, particularly children.