The Innocence Mission is a folk-pop group composed of husband-and-wife Karen (vocals, guitar) and Don Peris (guitar, percussion) and Mike Bitts (upright bass). The band met as teens in Lancaster, Pennsylvania, and released their self-titled debut album in 1989. Sun on the Square is their 10th studio album.

"Green Bus" is the album's lead single. When asked about the song's inspiration, Karen told Songfacts: "I always like color words. They seem to have an ability all on their own to make a visual world, especially the word green. The feeling of the song is a longing to give something of worth, and searching for that thing. And the bus may have come about because of the guitar rhythm I was playing, which maybe has a circular motion, but also just from the idea of a quiet place to view the city from and to think one's thoughts and decide where to go next."

Karen also illustrated the animated music video. She told us there wasn't really a green bus, but she enjoyed drawing the vehicles for the clip.

The Peris' teenage children also contributed to the album, with Drew Peris playing violin on this tune and "Sun on the Square," and Anna Peris adding viola to "Look Out from Your Window," "Shadow of the Pines," and the title track.