Blame it on the sliding doors.

Long stigmatized as terminally unhip suburban kid transporters, minivans have been facing a reckoning of sorts over the past year, with some manufacturers giving up on the segment altogether. Ford Motor Co. has discontinued making minivans to focus on a new trio of so-called crossovers -- models with sport-utility-vehicle proportions and practicality but generally smaller in size, with car-like handling and fuel economy. General Motors Corp. has announced it will stop producing minivans next year.

All told, the number of minivan models has shrunk to 15 for 2007, from a high of 21 in 2004, and six of those models have recently been discontinued or are slated to be soon. Sales are plunging so far this year, while sales of crossovers are surging.

The main reason? With so many vehicles aimed at families, one feature primarily distinguishes minivans from other, newer vehicle types: two sliding rear doors.

"Frankly, sliding doors are what give minivans open access, but that's what makes them uncool," says Detroit-based AutoObserver.com editor Michelle Krebs. "Practical, yes, but uncool."

Wes Brown, president of the Los Angeles-based automotive marketing firm Iceology, says the sliding door epitomizes the less-exciting realities of minivan ownership, compared to the proactive, vibrant images of go-anywhere SUVs and crossovers. "Ultimately, it's a symbol of being stuck in a rut of having a family," he says.

The remaining minivan makers have had to resort to drastic selling techniques to lure consumers away from shiny new crossovers and their cousins, including "tall wagons" like the Subaru Outback and "microvans" like the Mazda 5. Incentive spending on minivans averaged a whopping $3,900 in June, significantly outpacing the industry average of $2,483, according to consumer auto Web site Edmunds.com.

Even famously frugal Japanese companies like Toyota Motor Co. and Honda Corp., which sell the popular Sienna and Odyssey minivans, respectively, have greenlighted lucrative discounts this summer, prompting dealers to soap the windshields of new vehicles on the lot with rebate offers worth thousands of dollars.

While minivans range somewhat narrowly in price, starting around $20,000 and edging up to $40,000, crossovers range from $15,000 to well over $50,000. But minivans with third rows of seats and similarly sized crossovers are comparably priced. A top-of-the-line 2008 Buick Enclave CXL -- GM's newly released flagship crossover -- lists for $36,255, while a 2008 Chrysler Town & Country Limited minivan retails for $35,670.

Last year Americans bought 990,596 minivans, the first year since 1992 that annual sales fell below one million units, according to Edmunds.com. So far this year, sales are down 22%, potentially putting the industry on track to sell just 760,000 for the year. For the first half, minivans represented just 5.3% of total new-vehicle sales, down from 8.5% in 1995, according to the Power Information Network, a unit of J.D. Power & Associates.

Even for manufacturers with a history of innovation in the space, minivans are losing their luster. Earlier this year, what should have been Chrysler's triumphant unveiling of its revamped Town & Country model, a vehicle which helped turn around the company's fortunes in the 1980s, was overshadowed by its corporate divorce with DaimlerChrysler AG.

Volkswagen AG, maker of the iconic 1960s Microbus, decided to forgo resurrecting the model as it did successfully with the New Beetle -- despite having developed a well-received concept car. Instead, the company will use a modified version of a Chrysler Town & Country as the basis for its 2009 minivan.

This year, by contrast, crossovers are projected to be the fastest-growing segment of the otherwise soft American auto market. George Pipas, Ford's chief sales analyst, estimates industrywide sales of 2.8 million crossovers this year, up from a mere 500,000 in 2000, vastly overshadowing the market for minivans.

"It's true that we see a lot of traditional soccer moms with image issues tend to go towards crossovers," says Honda's truck-platform manager Eddie Okubo.

Some minivan makers have tried battling their image, attempting to make their offerings more hip, often to lackluster results in the market. Nissan Motor Co. tried offering a version of its Quest van with a dramatically designed center console. It sold dismally. Before deciding to abandon the segment, GM styled its last generation of minivans to look more like its SUVs. But the models sold poorly, eventually leading the company to emphasize crossovers.

"Every time anybody tried to be hipper, they failed," says AutoObserver.com's Ms. Krebs. "The core buyers want the same basics: a lot of room and more features. Anybody that's gone outside the formula hasn't been successful."

Manufacturers say that despite declines in the market, there remains a loyal group of customers -- particularly new families with younger children -- for whom minivans are a must buy.

"We believe that there's a core of customers for whom the rational -- the way they use the vehicle day-to-day -- is more important than the emotional," says Honda's Mr. Okubo. "For younger families, utility plays a major role. Sporting events, meets or games -- ultimately that lifestyle will never change."

Roomier cabins are indeed a major selling point. Steven Salazar, a 33-year-old firefighter in Austin, Texas, bought a 2007 Toyota Sienna in June to replace a seven-seat Honda Pilot SUV. "An SUV is pointless if you can't access the third row with car seats in the second row," says Mr. Salazar, who has two children and whose other family vehicle is a sporty Subaru WRX. "In any case, once you're going to be hauling around kids, the sex appeal of owning a car is gone," he says.

Even with a cohort of dedicated buyers, van makers aren't resting on their laurels. Chrysler's newest trick for its redesigned 2008 models is "Swivel 'n Go," in which the second row seats can turn around to face the third row. That feature also comes with a table that can be inserted between two rows, which Chrysler, a unit of Cerberus Capital Management LP, says merges a living room with a minivan.

Another source of innovation is rear-seat entertainment. Some of the newest high-tech, digital pacifiers offer dual screens that can operate independently such that one can be used to display a movie while the other is used for gaming. Chrysler is also launching a satellite television service for its 2008 line of minivans, the first of its kind.

Meanwhile, Ford unveiled its largest crossover entry yet in January, when it showed a 2009 model year vehicle called the Flex. The vehicle will have a third row of seats and meld aspects of a minivan with design of popular vehicles like the Mini Cooper. Features include a panoramic sunroof that occupies nearly the entire roof, an optional rear-seat refrigerator and versatile storage compartments throughout.

It doesn't have a sliding door.