Whether those two goals are compatible remains to be seen.

The government has tested the Registered Traveler card in five airports, beginning in the summer of 2004. Now the Transportation Security Administration wants to turn the program over to private companies.

On Friday the TSA announced the Registered Traveler program it envisions would let frequent fliers go through airport security lines more quickly if they pay a fee, pass a government background check and submit 10 fingerprints. The program is expected to be rolled out gradually to airports beginning July 20.

But the TSA also would like companies to offer more in-depth security background checks. As an example, the agency said the companies could use commercial data authorized by customers.

Carter Morris, who heads a group of 60 airports advocating the Registered Traveler program, said it remains to be seen whether that requirement will hamper it.

"It's a little early to say whether the whole program hangs in the balance," Morris said. "The vendors are worried that it adds cost to their business model."

The TSA also said it wants companies to offer improved screening equipment for security checkpoints or to pay for more screeners, and will give the companies special screening lanes in exchange.

Steven Brill is the media entrepreneur who heads Verified Identity Pass, a private company that's running a test program at the airport in Orlando, Fla.

The company charges $79.95 for the card, which allows card holders to use a fast security lane at the airport.

Brill said the company wants to install a shoe scanner - a plate on the ground that travelers would stand on as they put their Registered Traveler card into a kiosk. The kiosk verifies their identity and the shoe scanner looks for explosives.

The TSA, said Brill, is "willing to provide new benefits, and they invited us to provide new ways to provide them comfort."

TSA chief Kip Hawley has said Registered Traveler's benefits could include passengers not having to take their shoes or coats off or removing their laptops from their cases.

The program is intended to let frequent air passengers avoid delays and to free up security screeners to focus on other travelers.

Bruce Schneier, chief technology officer of Counterpane Internet Security, Inc., said he'd love to have a Registered Traveler card, but he doesn't think it adds much to security. He said it might enable terrorist leaders to find out if their operatives are on the terrorist watch lists that Registered Travelers are compared against.

"This is an easy way to test if your potential mission-goers have themselves on the list," Schneier said.