(FORTUNE Magazine) – Come into my portal, said the spider to the fly. In Schiphol Airport in Amsterdam, before boarding a flight to Singapore, I picked up a copy of the International Herald Tribune. I started on it above Austria, reaching the stock pages somewhere over the Balkans. Since I wasn't about to throw myself out of these windows, I started to check out yesterday's damage. Immediately I was lost. I couldn't find my stocks. I couldn't for the life of me remember whether I should look for AT&T with other acronymic A's or a little bit south with other Americans; whether Alcoa was alphabetized as written or would be found an inch below, under Aluminum. Companies' positions vary depending on the newspaper, and I couldn't remember which variation I held in my hands. Disoriented, I realized that it had been months since I had checked my stocks in a newspaper. I was used to checking them on America Online.

The next day I met up with a cousin, a consultant. He has a heavy newspaper and magazine habit and said he had been sure the Net would never change it--but it's starting to. With PointCast on his box at work, he no longer reads the paper for stocks and headlines: "Now I read it more to get a world view and for entertainment. I didn't think anything of it when I started using services like PointCast. But I did surprise myself when I started reading traditional publications online, though I haven't switched entirely."

Those anecdotes hint at what's behind one of the hottest strategies in the online business world--and not just there. The word that describes the strategy is "portal." It refers to a company's trying to position itself as your value-adding (and therefore fee-collecting) gateway to some place where you'll spend a lot of time and probably a lot of money. It's used mostly with reference to online services and sites on the World Wide Web: Yahoo, Lycos, AOL, and other virtual places want to be your portal to the Internet, your everyday first stop, your rabbit hole to commerce's newest wonderland, your neighborhood, and also your Virgil, your guide.

Over the portal to Hell, through which Virgil led Dante, were the words Lasciate ogni speranza, voi ch'entrate, "Abandon all hope, ye that enter here." Wannabe portals don't want you to abandon hope, just other portals, becoming loyal to one. Then you will see its ads, as you do billboards along your regular commuting route. You will collect your mail there, read a weather forecast from the source the portal chooses, ditto news, scores, and stock quotes, enter shops via its doorway--and all these services will pay for the privilege.

What makes this significant is the fact that the gatekeeper/guide strategy is hot off-line too. Citigroup wants to be your portal to the wonderful world of financial services. Gap wants to be not just your jeans supplier but your fashion guide. Martha Stewart and Ralph Lauren want to sell not just magazines and shirts, but also a full lifestyle of line extensions.

So this is more than a nerd's land rush. Big forces are at work, and if they're not motivating you, chances are they're attracting one or more of your rivals. First: A number of dislocations have jarred loose traditional connections between consumers and suppliers. There's the opening of cyberspace. "Customers new to purchasing online are receptive to forming new relationships," writes Jeff Bezos, CEO of Amazon.com, who must know my cousin. Add deregulation: In telecommunications, for example, where once there was just one doorway--in the U.S., Ma Bell--there are enough for the set of a Feydeau farce. In financial services, combine deregulation (both intranational and international) with high-speed, cheap data processing and a tax-subsidized explosion of investment in mutual funds and the result is that banks, brokerages, insurance companies, or amalgams of the three each hope to be the center of your newly complex financial life. So old relationships are up for grabs, and new technologies make it possible, in theory at least, for a company to become a clearinghouse for your life as a consumer.

Second, there's all kinds of evidence that we want ways to simplify our lives--and what simpler simplification than to turn big pieces of it over to a trusted guide? Buyers are more sophisticated than ever, but they are also overwhelmed by the choices their sophistication spawns. Says Bob Frisch, a partner at Andersen Consulting: "Five years ago, in most American towns a cup of coffee was a cup of coffee, and your options were cream and sugar. If my dad heard the guy ahead of him in line order a doppio latte skinny with arabica beans, it'd be, like, what the hell?" Today if you want call waiting with antilock brakes, free checking, a 56K internal modem, and extra cheese--someone's got it. According to the Yankelovich Monitor survey of consumer attitudes in 1996, fully 73% of Americans said, "Life is too complicated," up from 58% in 1985. In a fashion victim's cri de coeur, Edina Monsoon, the protagonist of the British sitcom Absolutely Fabulous, wailed: "I don't want more choice; I just want better things."

Third, we're pressed for time, with more of us working than ever, and working harder--in the past month alone, three working women have said to me, "What I need is a wife." While we rush through the supermarket in record time, its shelves glitter with a record number of varieties of extra-virgin olive oil. As we try to cope, Frisch argues, "brands have taken on an additional function. They have become a way to navigate through an increasingly complex array of choices; they're not just a mark of quality." On the loose, confused, and rushed, buyers are ready for a "place" that organizes their world.

But what makes a portal work? What makes it not just a toll taker but something that adds value? Why choose one door over another? There is actually a body of knowledge about what makes a portal successful, because though the portal strategy is hot, it's not new. Internet portals are the newest coil in a long skein of similar schemes to capture customers--to, in effect, own them.

You can go a long way back. Among the most successful and long-lived portals in business history were the great fairs held in the Champagne region of France in the 12th and 13th centuries. For about 200 years they were the places to do business in Europe. All the continent's goods--the silks and oils of the south, the furs and grains of the north--came here to be sold and bought. These were wholesale markets, not retail--but they were the Comdex of medieval business-to-business commerce; everyone who was anyone had to come.

The fairs--there were six--lasted two months each, and the secret of their commercial dominance was what happened in the second month, when the selling of goods died down and was replaced by a settling of accounts. According to Fernand Braudel, the great historian of early capitalism, "The originality of the Champagne fairs lay less in the superabundance of goods on sale than in the money market and the precocious workings of credit on display there." Financiers and bankers, mostly Italian, set up tables and exchanged currencies, bought and sold short-term credit instruments, even did a little arbitrage. Double-entry bookkeeping hadn't been invented yet, but just about every financial instrument known today (except those that bring down hedge funds) had been. The fairs eventually declined, partly because new land and sea trading routes opened up, but their central role in finance persisted long after they ceased to be the center of trade in goods. That suggests, Braudel says, that the fairs became portals not because they aggregated stuff but because they provided an efficient mechanism for performing transactions and obtaining financial leverage.

That's the key sentence, and you just read right over it. Anyone can amass cool stuff. What makes a portal a portal isn't the stuff; it's the fact that it's easier and more valuable to do business within its doors than without. Aggregation gets you in the game. To play well you need financial services; quality assurance and navigability through choices--the two brand functions; and something more--a reason that this portal's collection of services and brands is worth paying for.

Think, for instance, of another portal in business history: Sears Roebuck. General Robert Wood--who masterminded Sears' transition from catalog merchant to retailer, officially ran the place from 1928 until 1954, and was puppeteer even longer--didn't use the word "portal," but that's what he had in mind when he said Sears would be "the purchasing agent for the American people." And it was, dominating retailing as no store had, has, or will: By 1964, Sears was bigger than its five nearest competitors combined.

Wannabe cyberspace doormen might study how Sears exploited two different land rushes. The between-wars migration from farm to city and the postwar diaspora from city to suburb, like today's technological changes, jarred people loose from traditional buying habits. Sears won their confidence by vouching for its merchandise--money-back guarantees were a Sears invention--and by making the store and its house brands more important than the identity of the manufacturers of the goods it stocked. Sears later became so uncool that it's hard to imagine or remember that its name once embodied a sought-after lifestyle, a set of middle-class aspirations. (Now, no longer a portal, Sears touts other brands.) Sears also offered the crucial element of financial services. Sears beat Main Street because at Sears you could buy hardware, dinnerware, and underwear, and pay just one bill.

It wasn't just Kmart and Wal-Mart that straitened Sears' portal. BankAmerica hurt Sears too. In The Big Store, which chronicles Sears' attempt to transform itself in the mid-1980s, Donald Katz writes of "the revenge of the small shops": Little stores, in malls that Sears anchored, nibbled away its business. The mall itself became the portal. That wouldn't have happened without Visa and MasterCard--payment and leverage mechanisms that allowed customers to shop at lots of different stores but pay just one bill. Sears itself recognized the problem: Though in 1972 more than half of American households had a Sears credit card, Sears rolled out the Discover Card in 1985 so that customers could write checks to Sears even if they didn't shop there. But it was too late.

Portals work when you can't imagine life without them. That hasn't happened yet online--of the portals there, AOL, the Sears of cyburbia, shows the most stomach for creating self-branded online products. None have invented a payment system that leverages the consumer's time or money; shopping online mostly involves endlessly entering and reentering credit card numbers. The pornography sector--often a business pioneer--has systems that allow someone who is a "member" of one site to enter others without reestablishing his age or creditworthiness--an added value if you covet speedier smut. Amazon.com knows its customers, their tastes, and their credit records.

But would-be portals haven't shown why it's better to shop from inside than outside; likewise, financial supermarkets have barely begun to fulfill their promise of speed, ease, and power. Till they deliver on quality, navigation, convenience, and leverage--as well as aggregation--portals will fall short of owning customers.