"Song for Ten" is an original song composed by Murray Gold for The Christmas Invasion, and is named after the Tenth Doctor who made his full-episode debut therein. Performed by Tim Phillips, the song is heard on the soundtrack as the Doctor chooses his defining style of dress for the first time (after spending most of the episode in pyjamas and a housecoat), and later joins Rose Tyler and her family for Christmas dinner.

This was the first original song composed for the revived series, and the first original song composed for Doctor Who since the untitled rap song featured in the 1988 story The Greatest Show in the Galaxy. Since "Song for Ten", a number of episodes have featured original songs. Unlike the songs that followed, however, "Song for Ten" was extra-diegetic — meaning that there was no indication of it being heard by the characters in the narrative. One line of the song, "Have a good life, do it for me" paraphrases the Ninth Doctor's farewell to Rose in The Parting of the Ways.

To date, four versions of this song have been heard. Phillips' version, which has not been commercially released, was a relatively short recording and the only one so far heard on the series proper. When the time came to compile the first of the Doctor Who soundtracks, Gold chose to have Neil Hannon re-record the song, and expanded it to include new lyrics referencing Rose's disappearance in Doomsday. Around the time of the CD's release, a special charity concert of Doctor Who music, later chronicled in the Doctor Who Confidential episode "Music and Monsters", included a performance of the song (with some lyric changes and an extended ending) by Gary Williams. In July 2008, Phillips performed the extended version (which featured the same basic arrangement as the Williams performance, except with slightly faster tempo and a restoration of some of the changed lyrics) for the first Doctor Who Proms concert. Although broadcast on BBC Radio, this performance was omitted from the edited version of the concert released on DVD as an bonus feature with The Next Doctor in 2009.

The song has appeared in the show's incidental music as a major theme for The Tenth Doctor in orchestral form. Alternative versions of the song appear in School Reunion (over the final scenes), The Idiot's Lantern (over the final scenes), Love & Monsters (throughout), Fear Her (throughout the final minutes), Army of Ghosts (over the pre-credits monologue and just after the opening credits), Journey's End (as Rose hugs the Doctor, and as Sarah Jane, Jack, Martha and Mickey leave) and also briefly in The End of Time.