Chicago's bass player Peter Cetera wrote this and sang lead. Cetera specialized in ballads, adding variety to the band's sound which featured many more rock-oriented songs, often written by Terry Kath or Robert Lamm.
Cetera's ballads quickly became the band's biggest hits, with "If You Leave Me Now" their most successful song to that point, topping the charts in the US and UK. Of course, their record company wanted more of where that came from and kept pushing the Cetera songs - the big hit from their next album was his tune "Baby What a Big Surprise." The group found a new audience and became much more successful, but they also got earmarked as a soft rock group, which took the focus away from their grittier, horn-heavy songs. This became a point of contention for Chicago's famed section, especially trombone player James Pankow
, who recalls constant battles to get the horns higher in the mix from that point forward.
When Cetera left Chicago in 1985, his hits didn't stop: In 1986, "Glory Of Love
" went to #1 US and his duet with Amy Grant, "The Next Time I Fall
," made it to #4.