(MONEY Magazine) – It's an all too familiar scene to anyone with a driver's license. You're cruising along, maybe too relaxed, and it happens: A patch of ice, an unexpected puddle, whatever, and the car fishtails. Your heart jumps to your throat, and now you're fighting the wheel, trying to avert the spinout that your brain--in fast-forward--can already see: the rollover in the ditch, the nauseating crunch of metal.

What if there were a way to dramatically rewrite that scene? The vehicle hits the ice, a dashboard light flickers and, before you even have time to react, you're back on course and in full control--an accident avoided. With an electronic stability-control (ESC) system, you can do exactly that--avoid spinouts, prevent rollovers, save your neck and even your life.

SUV buyers, especially those who live in foul-weather climes, should consider stability control a must-have. But any driver, in any weather, in any type of car or truck, will be safer with this technology in his or her corner.

Here's why you need it, how it works, how much it costs and who offers it.

WHY YOU NEED IT

From its first appearance in Mercedes, Cadillacs and Corvettes around 1997, stability control has shown great promise in preventing the skids, spins and rollovers that lead to thousands of injuries and deaths every year. But until recently, no hard data were available to prove it.

Now two studies from Europe and Japan--where consumers have more widely embraced the systems--confirm what I've long believed: that stability control may be second only to seat belts in safeguarding drivers and passengers.

Toyota found that electronic stability control reduced single-vehicle crashes in Japan by a remarkable 35% and head-on crashes by 30%. And in the European study, Mercedes-Benz, whose lineup has sported ESC as a standard feature since 1999, reported a 29% drop in single-vehicle accidents; crashes of all types fell 15%. Those kinds of results could prevent as many as 6,000 of the nearly 43,000 crash-related deaths each year in the U.S.--dramatically more than air bags, which have saved about 800 lives annually since 1987, according to the National Highway Transportation Safety Administration (NHTSA).

HOW IT WORKS

In an ESC system, which evolved from anti-lock brakes, sensors monitor everything from steering-wheel position and tire speed to the centrifugal forces your vehicle undergoes while cornering. If the sensors detect that a driver is about to lose control, microprocessors automatically apply individual brakes and/or reduce engine power. Don't confuse ESC with primitive "traction control" systems, which can only stop wheels from spinning. ESC is vastly more sophisticated, able to correct your course with microchip speed and put you back in full control.

Don't expect the system to rewrite the laws of physics--it won't let you make a turn at 80 mph that's designed for 35. But the technology works consistently and reliably. And unlike air bags, which minimize injuries only after the fact, ESC is pre-emptive--an electronic guardian angel that steps in to avert potential disaster. "The safest accident is one that doesn't happen," says Jim Khoury, manager of advanced development for General Motors, which offers its ESC system, Stabilitrak, on more than a dozen models.

A NO-BRAINER FOR SUVs

A common misconception among SUV owners is that four-wheel drive covers all the safety bases in foul weather. The truth is, four-wheel drive boosts traction during a straight-line acceleration, but when you're turning or stopping, it does almost nothing to improve stability or safety. That's why manufacturers and safety groups see ESC as the perfect prescription for SUVs, whose tippy stances and tricky handling in emergencies make them prone to rollovers, often with fatal results. More than 60% of all SUV deaths are caused by rollovers, compared with just 24% of deaths in passenger cars. All told, rollovers account for just 3% of all accidents but nearly 25% of all crash fatalities, or roughly 11,000 deaths last year. And nine in 10 rollovers occur when a driver can't keep the vehicle on the road, exactly the situation in which ESC excels.

In the latest ESC development, SUVs from Ford and other automakers have added an extra sensor to recognize impending rollovers and deploy side-curtain air bags before the vehicle can flip. Volvo's XC90, the first SUV from Ford's Swedish subsidiary, can actually pre-empt the rollover by braking individual wheels to keep the vehicle right-side up; ditto for Lincoln's Navigator and Aviator.

Leading safety advocates believe ESC systems will decrease the rollover risk posed by SUVs. Brian O'Neill, president of the Insurance Institute for Highway Safety, wants to see stability control become standard on all SUVs. Yet NHTSA, the federal agency that sets auto safety rules, has been more cautious. The agency says that a shortage of real-world accident data, and the variety of ESC designs on the market, mean it's withholding judgment for now. It adds that a stability-control study is a top agency priority, with recommendations expected in the next two to three years. Meanwhile, the National Transportation Safety Board, a federal board acting in an advisory capacity, has strongly recommended that NHTSA require stability control on vehicles if its upcoming study proves ESC's benefit.

While cars roll over far less often than SUVs, they're not immune from sliding off a slick highway. It's telling that most sports cars, whose low centers of gravity, sticky tires and taut suspensions make them among the most sure-footed vehicles, rely on stability control for an extra margin of protection.

WHERE YOU CAN GET IT

So which cars give you stability control? If you're buying a pricey sports car, luxury car or SUV, chances are good that an ESC system is either standard or optional; Acura, Audi, BMW, Cadillac, Infiniti, Jaguar, Lexus, Mercedes and Saab have made it standard on all or most of their models.

Among lower-priced brands, Volkswagen leads the way, offering what it calls its Electronic Stabilization Program (ESP) on its entire lineup, either standard or as a $280 option. That makes it among the most affordable, since ESC systems typically range from $400 to $1,100 as stand-alone options. When it comes to U.S. automakers, Chrysler trails the pack badly: It offers the safety feature on just one model, the Crossfire sports car. (For a list of vehicles that offer stability control--and what each automaker has dubbed its ESC system--see page 134.)

The problem, says Bill Kozyra, CEO of Continental Teves North America, a leading stability-control manufacturer, is that too many consumers don't know the systems exist or how well they work.

Manufacturers, under enormous pressure to keep prices competitive, are loath to add expensive standard equipment that consumers aren't clamoring for. "Personally, I would like to see it on all cars, but it's hard [for many automakers] to justify on lower-priced models" due to costs, says Fred Heiler, a Mercedes spokesman.

Instead, automakers make it optional equipment. Unfortunately, they often "bundle" systems with other extra-cost features in a package that makes the price of entry even steeper. As a result, only six in 100 new cars leave dealerships equipped with an ESC system today. And that's discouraged automakers all the more.

Take the Ford Focus. Starting at $13,270, the popular compact was the most affordable car to offer a stability-control system. But when only 2% of buyers anted up $1,200 for the admittedly pricey system last year, Ford decided to drop it on 2004 models.

Despite the potential of ESCs to prevent rollovers, it's been a hard sell even to Ford's SUV buyers--a group one might have expected to embrace it following the public anxiety over the Explorer and Firestone rollover scandal. The company offers its system, called AdvanceTrac, as an option on the Explorer, the nation's best-selling SUV. But the $795 package includes features you may not want, like a towing package. You're also forced to shell out an additional $120 for adjustable pedals, designed to benefit shorter drivers. So whether it's cost, lack of knowledge or plain indifference, only 3% of Explorer buyers have opted for AdvanceTrac.

I can't blame a cash-strapped consumer for passing on yet another expensive option. But I've little patience with people who talk a good game about auto safety and then blithely skip stability control in favor of frippery like heated seats or a fancy audio system.

After years of testing these systems, from icy test tracks to real-world rainstorms, I believe stability control is far more likely to save your bacon than any air bag. Automakers should offer it on every car and truck, at a reasonable cost. And consumers should demand it.