DETROIT - The Buick Enclave crossover concept vehicle shown at the Detroit auto show is "99 percent" similar to the production version, says Robert Lutz, GM's vice chairman and global product chief.

One difference: The concept version seats six; the production version will seat seven.

Ed Welburn, GM's vice president of global design, says the Enclave's new interior style, called "Heritage Forward," uses wood and leather and has adjustable individual seats. Like Buick's new Lucerne sedan, the Enclave has the brand's signature portholes in the front fenders.

Steve Shannon, Buick general manager, says, "The Enclave's SUV-like shape and handling will be key selling points. Then when you add Buick's quietness and tuning - nobody has anything quite like it."

The concept version has 21-inch tires and seven-spoke wheels. It has a 3.6-liter engine with dual-overhead camshafts and variable valve timing. The 270-hp engine is paired with a six-speed automatic transmission and features all-wheel drive and four-wheel independent suspension.

The production Enclave replaces the Rendezvous and Rainier. It is expected to go on sale in early 2007. It is being developed on the Lambda vehicle architecture.

Shannon wouldn't discuss pricing but said competitors likely will include the Lexus RX 330 and Acura MDX. The RX 330 retails at $38,465, and the MDX is priced at $37,740. Both prices include shipping.

GRAND BLANC, Mich. -- General Motors will phase out Buick's Rendezvous and Rainier next spring and replace them with the near-luxury Enclave crossover.

Brian Bowden, Buick's marketing director, said the Enclave will be a 2008 model and will be sold alongside remaining 2007 Rendezvous and Raniers.

GM plans to end production of the Rendezvous crossover at the end of 2006 at the Ramos Arizpe, Mexico, plant. Production of the Rainier SUV at GM's Moraine, Ohio, plant is expected to end next summer.

GM plans to build the Enclave at its new Delta Township plant near Lansing, Mich., on the Lambda crossover architecture. Other Lambda vehicles will be the 2007 Saturn Outlook and the 2008 Chevrolet Acadia.

Bowden said Rainier sales will be absorbed by its platform mate, the GMC Envoy.

Design, it is often said around Detroit, is the road to recovery for the domestic industry. An automaker with a solid base of loyal customers might get away with a dull design that sells on brand-name reputation alone, but if in trying to overcome a dulled image—or retrieve lost customers—it all has to start with eye-catching design.

To that end, two of Detroit’s historic luxury brands rolled out design concepts at the North American International Auto Show striving to restore a sense of luxury and elegance to their marques: The Buick Enclave crossover utility is a thinly veiled preview of a production model coming in 2007, while the Chrysler Imperial concept represents yet another effort to define a halo car for that brand. After this year’s round of domestic auto shows ended in April, these concepts were made available to the press in the outdoors for the first time.

The Buick Enclave concept car wasn’t running the day we went to drive it, during a short period when it had finished its rounds in auto show displays but had not yet begun touring golf tournaments as it will this summer. A part had broken, and—being a one-off show machine with no parts inventory on hand—it was disabled just long enough to keep us out of the driver’s seat.

This was not quite as big a problem as you might imagine. Much as we prefer to see cars in motion, this one isn’t really so much a driver’s vehicle as one to look at, admire, sit in, talk about. Sure, it’s got the “high-feature” variable valve timing twin-cam 3.6-liter V6 (good for an estimated 270 hp), six-speed automatic and all-wheel drive, but we can wait to experience those in the production models (which will also offer a V8 option).

The point here is the design. Enclave is the design icon for Buicks going forward, and an elegant statement it is, one that has been well-received everywhere it has gone since being revealed at the Detroit show in January. From its dark-nickel-finished waterfall grille, through the portholes on the hood and back to the tailgate proudly emblazoned with the Buick tri-shield, it sets the bar high for a future of Buicks that aim to restore the marque’s luster in the near-luxury battleground.

So our disappointment that it wasn’t running had more to do with being unable to get it out from under a tent and see daylight reflecting off its surfaces.

Those surfaces, explained Mike Kutcher, program manager for the concept car, are exactly those of the production model. “We had to build this one in a hurry—it was scheduled into our auto show program late in the game—but we were working from production math. The surfaces were all defined; we just had to execute it. It’s fiberglass rather than metal, but it’s the finished styling.”

Some exterior trim may differ from what you see on the show car, but you’re looking at the shape that will appear in showrooms this fall. Similarly, the interior has a lot of handwork in it—wood trim done by carpenters, French-stitched leather—that reflects Buick’s aims in terms of fine detailing and precision, but won’t be exactly replicated in production.

The word “enclave” represents an enclosure, a retreat if you will, from the surrounding world. Inside an enclave one might find religious monks, an ethnic group, or a family choosing to shut themselves in and the rest out. The Enclave has six seats, each of them designed to provide private space for its occupant, so while the vehicle as a whole promises the isolated, calm retreat many seek on the road, each seating position might be regarded as an enclave of its own.

“Passengering” in the Enclave may turn out to be as special an experience as piloting it has the potential to be. Under the panoramic glass roof, each of the four rear positions has its own DVD player (the one for the front seat shares its screen with the navigation system and works only with the vehicle stopped and with the transmission in Park). The screens for the center seats are overhead and mounted on a bar that travels in a track above the windows, so they can be moved rearward to serve the rearmost seats. We thought this was just a concept car trick, but Buick says this feature will be “significant” (whatever that means) when we see the production model.

Kutcher noted many of the metal-finished surfaces inside and out played with a contrast of bright-finished chrome against a brushed-aluminum look, often on the same part (exterior and interior door handles, wheels, etc.). The four back seats all have access to their own tray tables, rather like those on a first-class airline seat (or a Jaguar Vanden Plas), and the seatbacks also have their own buckled, leather portfolios attached. These latter are not production features—expect more ordinary storage arrangements there.

Still, the Enclave, as big as a Mercedes R-Class, should be the standout design among the three vehicles built on this platform (the others are the Saturn Outlook and GMC Acadia). If the final execution is undertaken with the same level of attention to detail and indeed, pride in one’s workmanship that is evident in the show car, Buick will have raised itself a notch, from matching its Lucerne up against the Toyota Avalon to going head to head with the best-selling Lexus RX series.

Last week, it was the 2007 GMC Acadia, this week the 2008 Buick Enclave. Spotted on public streets in Michigan, this Enclave prototype shows just how close the production vehicle will adhere to the concept. Built on the same platform as its GMC and Saturn cousins, the Enclave is expected to go on sale next spring.