The world's biggest new pop star is a little bit country, a little bit rock & roll, and all control freak. What's behind her drive for success?

On a bright sunday afternoon in Los Angeles, Taylor Swift is on good behavior, as usual. In high school, she had a 4.0 average; when she was home-schooled during her junior and senior years, she finished both years of course work in 12 months. She has never changed her hair color, won't engage in any remotely dangerous type of physical activity and bites her nails to the quick. At 19 years old, she says she has never had a cigarette. She says she has never had a drop of alcohol. "I have no interest in drinking," she says, her blue eyes focused and intent beneath kohl liner and liberally applied eye shadow. "I always want to be responsible for the things I say and do." Then she adds, "Also, I would have a problem lying to my parents about that."

Swift has gotten far playing Little Miss Perfect — not only was her second album, Fearless, at Number One for eight weeks this winter, but she's enjoyed numerous perks, like a 10-day stay at the West Coast home of her childhood idols, Faith Hill and Tim McGraw, which is where she is today. The couple, who befriended Swift in Nashville, offered the use of their house while she is in L.A. appearing on an episode of her favorite show, CSI. The fact that Swift's first hit single is called "Tim McGraw" — a wistful, gimmicky ballad about a separated couple who recall each other by their favorite McGraw song — is a clue to her feelings about them. "I love Tim and Faith," she says, dashing about the house, which is utterly enormous, filled with gilt crosses and life-size Grecian statues, and worth about $14 million (Eddie Murphy is a neighbor, in a house "the size of a country," says Swift). "I think I like the bright colors in here better than the lighter ones," she says, critiquing the rooms, which seem to go on endlessly, like galleries in a museum. "I don't know. I go back and forth. You know when you walk into a furniture store, and you're like, 'Oh, that's how I'm going to decorate my house,' and then the next one you're like, 'No, that's going to be the way I decorate my house'?" She giggles. "I think when I do it, I'm going to be so indecisive."