Extract from Wikipedia: According to lead singer, pianist and songwriter Isaac Slade, the song was composed and influenced by his experience while working as a mentor at a camp for troubled teens.
The song was first featured on ABC's Grey's Anatomy, after Alexandra Patsavas, the music supervisor for the show, saw the band perform in Los Angeles. Alexandra then incorporated the song into an episode of the show's second season (first aired on March 19, 2006). After its usage in the episode, the song became a minor Hot 100 hit.
The song became an "unofficial theme" for the other members of the Grey's Anatomy production and it was decided that the song would be used in the main promotion for the third season in the show. Grey's Anatomy is credited with bringing popularity to the song.
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