"You're the Inspiration" is a song written by Peter Cetera and David Foster for the group Chicago and recorded for their album Chicago 17 (1984), with Cetera singing lead vocals. The third single released from that album, it reached number 3 on the US Billboard Hot 100 chart in January 1985, and also climbed to the top position on the adult contemporary chart at the same time. Peter Cetera re-recorded the song for his 1997 solo album You're the Inspiration: A Collection. That same year he also recorded a single version with the vocal R&B group, Az Yet.

Peter Cetera stated in a 2004 interview that "You're the Inspiration" started out as a song for Kenny Rogers. "David Foster called me up and he said, ‘I’m in the studio with Kenny Rogers, and he would like you to write a song for him.’ And I said, ‘That’s great! As a matter of fact, I’m leaving for Italy...’ I was going to Europe for something. I don’t remember [why]...and this was like nine o’clock in the morning. I said, ‘I’m leaving for Italy tonight around five o’clock. I’ll be there about two weeks, and I’ll call you when I come back.’ And he goes, ‘No, no, no, he means, like, now.’ (....) And so David was in the studio...and of course...you know, last minute. And so I said, ‘Alright, well you come over here right now, and we’ll see what we can do.’ So in the midst of packing, David drove out to where I was then living. And we basically, in about three hours, came up with a little chordal structure for “You’re the Inspiration,” which it wasn’t called that at the time. And we sort of made this little tape of this chord structure; I took it on the plane, [and] went to Italy. And, of course, lying in these beautiful baroque and marble rooms, and singing out the window...I was writing things about, ‘Michelangelo you should know, Michelangelo.’ And I came up with, oh...you’re the inspiration! [So, I] came back with the words, worked on this melody, and came back and presented the song. And [Kenny] basically didn’t have the time or didn’t want to do it. Good for me!", He then changed some of the words and recorded it with Chicago for their Chicago 17 album.

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