You're a chef. You've been banished to a remote island and your survival depends not on providing water, food and clothing for yourself, but on creating classical French cuisine. That's right-the natives are restless; they're hungry, and they want consomme julienne. They also want boned squab with truffles followed by poached pears in vanilla sauce. Trouble is, you're only allowed to bring one knife.

Which knife would you bring?

The answer is simple, according to the professional chefs I recently surveyed in Portsmouth.

According to Gary Caron, chef of The Dolphin Striker, the eight-inch chef's knife, also known as a French knife, is by far the most versatile. "The shape of the blade makes it ideal for a variety of tasks," he says. The heel is sturdy enough to chop poultry carcasses, the middle arc of the cutting edge contacts the cutting board perfectly for precision vegetable cuts, and the tapered tip is great for peeling fruit.

Chris Stone, kitchen manager of Colby's (formerly Roxanne's), agrees. "Having the right eight-inch chef's knife is like having a set of eight knives," says Stone. "I can use it for pretty much every task, from butchering beef to cutting julienne vegetables." ("Julienne" refers to a long, thin cut of vegetable.)

A chef's knife is also well suited for unconventional jobs; the side of the blade can be used as a mallet to flatten cutlets of meat and to smash garlic, the blade can be used to scoop up piles of minced herbs and vegetables, and the back of the blade (the spine) can be used to tap a sieve when straining soups or sauces. And, though not recommended, many chefs will admit to using the heel of the blade to punch open cans when an opener can't be found. A chef's knife is available in a variety of blade lengths, from six to 14 inches, with the eight-inch being the most common.

Shopping for a blade may seem overwhelming for the first-time buyer. Caron was once so frustrated with the blades on the market that he dabbled in forging his own. "I was looking for specific characteristics-blade shape, comfort-and I was looking into custom knives and thought, 'I could make a knife if I wanted to.'" His first attempt was "horrendous," he says, but he eventually produced some worthy blades. In the meantime, the knife market blossomed, and today, says Caron (who now only pursues knife-making as a hobby), "it's not hard to find a blade that feels right."

When shopping for a blade, Caron recommends handling the knife in-store to get a feel for the weight and substance. A good quality knife will feel substantial in the hand. The handle in particular will feel comfortable and sturdy. As a rule, look for a blade that extends at least three-quarters of the way into the handle. This extension of the blade, called the "tang," lends weight and balance to the knife, and can range from a simple rod, known as a "rat tail tang," to a full tang, in which the metal is visible from all sides of the handle.

Good knives can be found at some department stores, at retail kitchen supply stores such as Kitchen Etc. (which is closing all of its stores-this is a good time to shop for blade bargains), and local shops such as Attrezzi, Strawberry Bazaar and City and Country offer good knives, but with a limited selection of one or two brands.

For a wider selection of brand names, local chefs suggest traveling an hour north or south. Stone has a few favorites. "Freeport Knife Company (in Freeport, Maine) is great, and I also like Stoddard's in Copley Plaza (Boston)," he says. William Sonoma also carries a nice selection, and if you have a chance to wander around Boston's Chinatown, you will find stores that carry conventional kitchen knives alongside cleavers, Samurai swords and sportsmen's knives. The frugal shopper can handle a few blades, then check local shops or buy factory-direct online for the best price. Attrezzi carries Global knives, City and Country carries Henckel and Oxo Good Grips, and Strawberry Bazaar carries Henckel, Calphalon and Oxo Good Grips, all at competitive prices.

As for brands, no two chefs seem to agree on which is best. Jacques (Desir?) Moonsamy, chef of The Metro, says he has faith in most German knives, citing W?sthof-Trident and Henckel as dependable brands, while Stone prefers Global (a Japanese company), whose knives are forged from one continuous piece of metal. Josh Lanahan, chef/owner of Saucy Grace, has had great luck with a little-known brand called Forschner, and jokingly tells colleagues who scoff at the bargain price of $45 (Henkels, W?sthof-Trident and Globals average in the $80-$90 range for an eight-inch chef's knife) "remember, the knife doesn't do the cutting, the chef does," but adds, "I wouldn't use them if I didn't think they were a great knife."

In addition to handle construction, pay attention to the blade. The blade should be constructed of material that takes and holds an edge easily, but also resists rust and corrosion. The best general-purpose blade is a combination of carbon steel and stainless steel. With the proper sharpening (using a sharpening stone to create an edge, and a magnetized, grooved rod known as a "steel" to maintain the edge), the knife will take and hold a razor-sharp edge without pitting and rusting. Sharpening can also be done by a professional grinding service. Both Stoddard's and Freeport Knife Company offer sharpening services, with prices ranging from $2 to $9, depending on the blade.

Avoid blades made with super-stainless alloy steel, which is often touted as needing no sharpening (the amazing Ginsu Knife, anyone?), but which is actually so hard that it is virtually impossible to sharpen. Also avoid blades made of pure carbon steel, which takes and holds an edge quite readily but corrodes easily, particularly when used on high acid foods such as garlic, onions and citrus fruits.

Happily most chefs aren't forced to choose just one knife for an entire culinary repertoire. In reality, there are several basic knives that even a home kitchen should include.

The knives listed above are some typically offered in an all-inclusive knife "kit." You can buy a full collection of knives as a set, saving money and time, but some chefs prefer to add knives one at a time to their collection, particularly since certain heavily utilized blades may require frequent replacement.