Carrie Underwood co-wrote "Cowboy Casanova," the lead single from her third studio album, Play On, and one of the biggest singles of her career, with Mike Elizondo and Brett James. Released in September of 2009, "Cowboy Casanova" became the fastest-climbing country single of the year and Underwood's eighth No. 1 hit. It's been certified double platinum and was nominated for an ACM Award. Below, Underwood and James discuss writing the tune.

Underwood: People are always asking about "Cowboy Casanova" -- like, who's that? And they try to make it about one specific guy in particular. But "country music" and "cowboy" are part of my vocabulary, so I'm not aiming that toward any particular football team or guy or anything! I sing country music, so I sing about cowboys. But "Cowboy Casanova" is about a type of guy -- not about a cowboy. I think of cowboy as being quiet and strong and rugged and good looking ... and having an inner confidence kind of thing. Not necessarily just boots and hat.

James: With "Cowboy Casanova," we started with a concept: How should we write about a "Cowboy Casanova"? What's the story we need to tell about this guy? And we decided that the way to tell it would be to warn women about him [laughs]. Because the singer, Carrie, puts herself in the place of the woman who's been burned by this guy, and she wants to warn other women about the evil of his ways.

Underwood: I think to every woman, this song would be telling a story about someone they know or met or has tried to pick them up in a bar. There's definitely guys in my past, even if it was a friend's boyfriend or something.

Everybody kind of freaked out at first [when we started working with Mike Elizondo, a rap producer who's known for hip-hop collaborations with artists such as Eminem, 50 Cent and Dr. Dre] ... and it was something that we did take into consideration, that people would be like, "What's going on here?" Everybody kind of flipped out over Mike, who I really like. They're like, "He's a rap producer!" Well, yes, he has done that. But he's also worked with Nelly Furtado and Pink and Fiona Apple. I'm just another name he's adding to his resume, of all different kinds of music. Mike's just a great figure in music. So it was really fun to add him to our team and see what we could come up with. It could've been a disaster, but it was not. We came up with something really fun and really different for all of us.

James: Mike really came in with a lot of the musical side of this song -- that whole beat, the electric riffs. He brought that in with him, and said he'd been thinking all day about this kind of groove. And the way Carrie and I work, we're both singers and come from the lyric point, so we both just started singing on top of what he was doing.

Underwood: It's really fun to bring new people into your world. You just kind of keep everything fresh and keep it new, for me and for the audience. Music is music. Great music is great music. I might get the chance to return the favor and go write for their world now.

This story was originally written by Marianne Horner, and revised by Angela Stefano.

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