For starters, it's hard to believe -- and wonderful to comprehend -- that Nonesuch is doing such a bang-up job in 2006.

Their roster is ever expanding from the Black Keys and Pat Metheny to Brad Mehldau and Sam Phillips, from Stephin Merritt to Shawn Colvin -- they are an impossible label to predict, but their track record of late is impeccable.

As for Colvin, it's been a while.

Other than a video called Live in Bora Bora, and a greatest-hits collection, she hasn't recorded an album of new material in five years.

But it was worth the wait.

Working with longtime collaborator John Leventhal (who in addition to being producer is a virtual one-man band, though drummer Shawn Pelton and Rick DePofi help out on percussion and horns, respectively), and Colvin co-wrote almost the entire album with him.

There are two covers -- of the Bee Gees "Words" and Paul Westerberg's "Even As We Are" -- Colvin wrote "I'm Gone" on her own.

Sonically, you already know what to expect.

This is an album drenched in acoustic guitars, some electric ones, gentle keyboards, and poignant songs.

Colvin always gets to the meat of the matter in her lyrics.

She trims it all back to the bone to see what's there, gleaming and gritty.

These Four Walls is a record of ups and downs, about taking responsibility and surviving one's mistakes.

Tracks like "The Bird," with its jangly, ringing, 12-string electric guitars and claims of regret, resignation, and responsibility is a love song, but one that is wholly original.

The characters are broken and while they trust in the redemption of love, they know it's just tough to get through: "What I like about time is it don't ask why/What I like about love is it makes me cry..." On the title cut, with only an acoustic guitar carrying her smoky lithe voice, Colvin states "I'm gonna die in these four walls/I've had enough and I've tried it all/I'll watch the day break and I'll see the night fall/In these four walls...Now I can see the life I have to make .

." Layered guitars, a mandolin, shuffling drums and Greg Leisz's pedal steel waft on in and carry it home.

The now-ubiquitous Patty Griffin and Marc Cohn make vocal appearances on "Cinnamon Road," the album's centerpiece but far from its best track.

Better are the sexy as all get out "Venetian Blue," the subtly yearning "Fill Me Up," which opens the set, and the poetic and utterly moving "Summer Dress." The two covers work alright, but they don't stack up to Colvin's and Leventhal's songs, which are more poignant, musical, and imaginative.

The rocking "Let It Slide" (with a guest vocal from Teddy Thompson) is an example of what Colvin and her voice do best -- emote matter of factly, where passion is a slow burn and precarious by nature -- and the tune's chorus is infectious.

While sonically and texturally there is not a whole lot different here, that's just fine.

When you can write and sing like Colvin can, all you have to do is keep putting the songs out there.

So many of her peers in the "grrrl revolution" of the '90s are struggling to find their way, while Colvin has been on hers continually, refining, recording only when she has something to say, and being so honest it's almost painful.

These Four Walls is an achievement, another step on a gloriously rocky road that is far from its end.