Toward the end she brought on the singer-songwriter M. Ward. (His strong but quiet opening set nearly inspired sectarian conflict: chatters versus shushers.) On “Creepin’ In” and “Hands on the Wheel,” his rumpled voice sounded great next to her smooth one. He appears on “Not Too Late,” and there’s no good reason why these two shouldn’t make an album together.

Have You Never Been Mellow? Or Pleasant or Sad?

O come let them adore her: Norah Jones. Her fans filled the Theater at Madison Square Garden on Wednesday night for precisely that purpose; at least one had come all the way from Brazil. (Or so he claimed, loudly, between songs.) According to her record company Ms. Jones is “the best-selling female artist of the 21st century,” and although she may encounter some competition in the next 90-odd years, the point is indisputable: she’s a star.

But she doesn’t make it easy for her fans to treat her like one. She’s a determinedly casual presence onstage. “We’re going to do another creepy one for you now,” she said, before one song; “We’re going to play a little lullaby for you now,” she said, before another. She has that famous voice, which makes it seem as if she’s simply exhaling the melody. And she has found an approach that works: her best songs are hugely pleasant.

All of this can make it hard for fans to act like fans. Early on, she asked, “You guys doing O.K.?” The crowd replied with a few seconds of applause, which ended as suddenly as it had begun. “You all stopped at once,” she observed, as if surprised that the crowd was so mellow and polite. Isn’t that a bit like Shane MacGowan wondering why his fans are so drunk?

No matter. Backed by a nimble band, Ms. Jones moved from guitar (she admitted, disarmingly, that she had only recently started playing it, and jokingly thanked her band mates for letting her practice it onstage) to piano and back again, alternating between the songs people wanted to hear and those they were willing to hear.

In the first category were “Don’t Know Why,” her 2002 breakthrough hit, and “Sunrise,” a lovely daydream from her country-influenced second album, “Feels Like Home.” Also in the first category were some songs from her recent album, “Not Too Late” (Blue Note), including the charming first single, “Thinking About You.” It’s no coincidence that these are slow jams, more or less: slow-burning love songs that practically cry out (though quietly) for wine and candlelight.

“Not Too Late” is, by design, the least pleasant of Ms. Jones’s three albums; it includes a couple of songs that seem to be about President Bush, “Sinkin’ Soon” and “My Dear Country.” She performed them both on Wednesday night, emphasizing the light comedy, not the heavy despair. “Who knows, maybe he’s not deranged,” she sang, inspiring an appreciative chuckle. There were a few excursions into jazz too: tasteful, competent, rather dull. You might understand why Ms. Jones gets sick of slow jams but you might also wish she wouldn’t.

Toward the end she brought on the singer-songwriter M. Ward. (His strong but quiet opening set nearly inspired sectarian conflict: chatters versus shushers.) On “Creepin’ In” and “Hands on the Wheel,” his rumpled voice sounded great next to her smooth one. He appears on “Not Too Late,” and there’s no good reason why these two shouldn’t make an album together.

There was a short encore and then, after a cover of Tom Waits’s “Long Way Home,” the show was done. Maybe people would have brought her back for a second encore, but they didn’t get the chance: she had barely left the stage before the lights went on and the fans — as mellow and polite as the singer they love — began to wander out.