If it seems like airports are a lot more crowded these days, there's a good reason: US Department of Transportation statistics show an average increase of almost 20 million passengers per year boarding planes at US airports during the 1990s. The swell has given rise to longer lines at checkout counters and border controls and spawned an organization that hopes to help solve the problem.

The Simplifying Passenger Travel initiative (www.simplifying-travel.org ), which launched last year, is backed by the International Air Transport Association and the Airports Council International, among other groups. Its aim? To boost the capacity of existing terminal space by reducing the amount of time passengers spend queuing up for airport formalities. To do this, the group has looked to create standards and coordinate the technology efforts of airlines, tech firms and other parties in the travel industry.

Already the list of these efforts runs long. Self-service check-in kiosks are becoming commonplace in major airports as electronic ticketing becomes increasingly popular. (A new service from British Airways even allows e-ticketed passengers to check in via WAP-enabled mobile phones before arriving at the airport.) Some airlines are testing the use of radio frequency chips in luggage tags to lick the problem of lost bags, and Swissair is using the same wireless technology for fully automatic hands-free check-in at the Zurich airport as passengers equipped with special "e-pass" cards move through immigration checkpoints.

"First-generation systems, such as the US INSPass program, have been around for many years," says SPT Program Director Thomas S. Windmuller, referring to automated immigration kiosks in use at some US airports. "The key to getting to the next stage is to establish or refine programs in accordance with agreed global standards and procedures so they can be linked together in ways that benefit passengers at both ends of the journey," Windmuller says, adding, "despite the success of such programs, they are not yet compatible with one another on an international level."

As SPT pilot projects move forward in London, Amsterdam and Sydney, attention will be focused on what Windmuller sees as the biggest hurdle standing in the way of this holy grail of ground services: "The development of the business case to justify investments in these systems. We see this coming from the increased efficiency that SPT will bring."

INSPass, which stands for Immigration and Naturalization Service passenger accelerated service system, is a good example of how information technology is already greasing the wheels of automated border crossings. The program combines smartcard technology with handprint scanners that confirm the identity of the cardholder, allowing eligible frequent travelers to bypass normal immigration controls. A similar system is being implemented in Canada, and smartcards are used to expedite travelers across the busy causeway that links Singapore and Malaysia. In Australia, a virtual visa system that eliminates the need for a passport stamp has been in place since before the STP was formed.

But for all its ambition, SPT's push raises a bit of a Catch-22: The more successful it is, the greater the risk of privacy violation. "Individuals who decide to use such a system may well be giving up more than they are receiving in conveniences, time-saving and hassle-reduction," warns Beth Givens, director of the nonprofit Privacy Rights Clearinghouse.

Deborah Pierce, a staff attorney for the Electronic Frontier Foundation, articulates similar concerns: "Who has access to this information? Can the individual see what information is being kept on him or her and amend it if necessary? What other databases will all of this valuable personal information end up in? How will individual's travel itineraries be tracked and used?"

For SPT's part, Windmuller says, "it is essential to tackle these concerns head-on," with industry and government sponsors cultivating consumer confidence in much the same way banks have cultivated consumer acceptance of automatic teller machines.