Chicago is an American rock band formed in 1967 in Chicago, Illinois, calling themselves the Chicago Transit Authority in 1968 before shortening the name in 1969. The self-described “rock and roll band with horns” began writing politically charged rock music, and later moved to a softer sound, generating several hit ballads.
1980s: changing sound
Chicago XIV (1980), produced by Tom Dowd, relegated the horn section to the background on a number of tracks, and the album's two singles failed to make the Top 40. Chris Pinnick joined the band to play guitar and remained through 1985, and the band were also augmented by saxophone player Marty Grebb on the subsequent tour.Marty Grebb had formerly been with the Buckinghams, and before that had been Cetera's bandmate in a local Chicago area cover band called the Exceptions. The album peaked at No. 71 on the Billboard 200, and failed to reach gold certification by the RIAA. Believing the band to no longer be commercially viable, Columbia Records dropped them from its roster in 1981 and released a second "Greatest Hits" volume (also known as Chicago XV) later that year to fulfill its contractual obligation.

In late 1981, the band had a new producer (David Foster),a new label (Warner Bros. Records), and the addition of keyboardist, guitarist, and singer Bill Champlin (Sons of Champlin). Percussionist Laudir de Oliveira and Marty Grebb departed from the band. During Foster's stewardship, less of an emphasis was placed on the band's horn-based sound, being replaced by lush power ballads, which became Chicago's style during the 1980s. The new sound brought more singles success to the band.

Peter Cetera departure
Concurrently with Chicago's existing career, lead vocalist Peter Cetera had begun a solo career. He proposed an arrangement with the band where they would take hiatuses after tours to let him focus on solo work (mirroring that of Phil Collins and Genesis), but the band declined. Cetera ultimately left Chicago in the summer of 1985.