The 1967 film classic "The Graduate" opens with some unwelcome career advice for the newly minted college grad played by Dustin Hoffman. "Plastics," the older man counsels. "There's a great future in plastics." These days "plastics" has been replaced by computers and the Internet. As a result, the career paths for high-end salesmen and brokers will be transformed for some and become a dead end for others.

Thanks to the Internet, highly compensated sales positions may soon fall victim to the same sort of do-it-yourselfism that earlier erased hundreds of thousands of lower-wage jobs. Gas station attendants, bank tellers, telephone operators and typists all fell victim to automation and a penchant for penny pinching among business managers and informed consumers alike.

In the near future, more than 1 million sales and brokerage positions, which typically pay above-average wages without requiring a college degree, will become vulnerable as the Internet matures into an automated middleman that connects buyers directly to sellers.

Real-estate agents, stock brokers, travel agents and car salesmen all traditionally take a "cut" from the most important purchases made by most families. Precisely because the purchase of a home, car, vacation or investment program for retirement are important and appear complex, consumers have gladly paid prices padded with a commission that adds an extra 5% to 10% to the price a seller or producer otherwise would demand.

Efficient markets squeeze out the middlemen

Market intermediaries -- middlemen (or women) -- make their money by remedying (and sometimes by exploiting) the ordinary consumer's lack of basic information about who is selling what and for how much. The Internet threatens to cure this profitable market imperfection by giving consumers easy access to data on competing goods and services. Once that data is compiled by online brokers and made readily available, along with do-it-yourself instructions, the priesthood of the market intermediaries will be shattered forever.

This process of "disintermediation" due to the Internet already is sending shockwaves through industries that rely heavily on educated and upscale consumers. Merrill Lynch, the world's largest securities brokerage, is waving the white flag with respect to online trading. Last week, the brokerage firm stunned Wall Street by offering the public free access, during a four-month trial period, to the same proprietary stock research available to its wealthy and institutional clients.

Although Merrill Lynch described the move as a marketing strategy that would identify leads for its army of full-service brokers, it also represents a capitulation to the massive migration of young investors to online trading. Low-fee trades placed online with upstarts like E*Trade Group already represent 20% of all retail transactions, tripling in 18 months. At Charles Schwab, online trades have surged to 55% of total trades, reducing average commissions by $10 in just six months.

Unless the traditional brokerages get online fast and retrain their brokers to add new value -- perhaps as providers of comprehensive financial-planning advice -- their high-commission customer base will age and atrophy.

Another sign of the times was last week's announced acquisition of the nation's largest book distributor, Ingram Book Group, by Barnes & Noble, the nation's biggest bricks-and-mortar book retailer. Chief Executive Officer John Ingram said he simply could not survive in a world where mega-chains and online book retailers like Amazon.com become big and efficient enough to bypass distributors, buying books directly from major publishers. "The middleman was being cut out, and we're the middleman," Ingram said.

No more cold calls

If the nation's largest brokerage and book distributor are running scared, it may just be a matter of time before high-commission salesmen are reduced in number and forced to upgrade from supplying raw information to providing experience, advice or other services that cannot be offered online. In addition to the nation's more than 200,000 stock brokers and securities sales representatives, the most vulnerable middlemen include:

Real-estate agents

The nation's 285,000 real-estate agents maintain a kind of quasi-regulatory trade guild that shrouds the process in mystery. For example, only licensed brokers are allowed to list on Realtor.com, the Internet database of home listings run by the National Association of Realtors. This summer, I sold my own home "by owner" and got my asking price. The hardest part was cleaning it up for the open house. I paid a broker $200 to list it on Realtor.com, but that was better than signing away the standard 6% ($16,000) commission.

With billions of dollars in commissions at stake, and the process so easy to simplify, it is only a matter of time before an online entrepreneur develops a cost-efficient way to play matchmaker. Already, Microsurf.com, which also provides quote comparisons on mortgages and movers, is online with a database of homes for sale by owner.

Mortgage brokers

Shopping rates caught on even before the Internet onslaught. Now sites like Bankrate Monitor offer dozens of quotes from local lenders, including customized searches for special mortgage options. Before long, consumers will be able to research and apply for almost any loan without ever speaking directly to a sales representative or broker.

Insurance agents and brokers

The nation's more than 400,000 insurance agents are more vulnerable than real-estate agents because their product is even more of a commodity. Excellent online sites, such as Intuit's InsureMarket.com, make insurance shopping quick, easy and cheap, using extensive side-by-side quote comparisons. One result: The average price of term life insurance has dropped dramatically over the past two years.

Travel agents:

Even before the Internet, deregulation and price-shopping led airlines to cut commissions paid to the nation's more than 140,000 travel agents. Many agencies went out of business, and more will follow as services like Travelocity.com and Expedia.com use smart agents to track down the cheapest fares and even to assemble comprehensive travel packages.

The importance of universal access

Of course, dozens more sites have sprouted up that will to some extent undercut bricks-and-mortar retailing on everything from computer hardware, to kitchenware, to music. One troubling consequence of the "computer gap" between affluent and low-income households may be that the real-estate agents and other salesmen will continue to extract their "information fee" from less savvy consumers -- much as inner-city groceries charge premium prices.

Because the Internet is becoming increasingly important as an "information utility," finding some way to guarantee universal access -- as we do with broadcast television -- is one way to improve the private market's overall efficiency without resorting to more regulation.