They walk up to an ATM and press their thumbs on the screen. Out spits the cash.

New York? No. Chicago? No. The mountains and jungles of Colombia.

It’s one of the few places in the world where banks are using fingerprint biometrics, which verify people’s identities based on their unique physical characteristics.

Scanning fingerprints or irises to verify an ATM customer’s identity has yet to penetrate the U.S. banking market because of concerns about expense and privacy.

Customers must be convinced that the technologies provide more benefit than the card-and-PIN system, which works well, said John Hall, spokesman for the American Bankers Assn. The cards also serve functions beyond the ATMs, as debit cards and as advertising for the banks.

“Getting that wallet space is important,” said Bill Spence, a biometric expert with Campbell, Calif.-based Recognition Systems Inc.

However, companies that make automated teller machines have found budding markets for the fingerprint technology in South America, where citizens already are accustomed to the use of fingerprints for general identification, such as ID cards they carry.

Diebold Inc. of North Canton, Ohio, has supplied fingerprint-capable ATMs to a bank in Chile that is using them in a pilot project. Last year Dayton, Ohio-based NCR Corp. installed 400 of them in Colombia.

NCR's Aileen Hird tries a fingerprint verification ATM at NCR in Dundee, Scotland. Scanning fingerprints or irises to verify an ATM customer's identity has yet to penetrate the U.S. banking market because of concerns about expense and privacy.

BanCafe, Colombia’s fifth-largest bank, bought the ATMs at the end of 2002 for added security for coffee growers and to get them to open accounts. The growers wouldn’t need to carry ATM cards, which can be a lure for thieves.

“Biometrics is certainly the most secure form of authentication,” said Avivah Litan, an analyst with Gartner Inc., a Stamford, Conn.-based technology analysis firm. “It’s the hardest to imitate and duplicate.”

About 350 banks in North America are using Diebold’s hand geometry systems to clear customers into vaults so they can open their safe-deposit boxes. At Zions First National Bank in Salt Lake City and South Carolina Federal Credit Union, users place their hands on a screen, which reads the width of the palm, length of fingers and other points of the hand.

Finger scans – in which people are identified by multiple points on the finger rather than fingerprints – are being used at grocery stores and by people renting lockers at some airports, train stations, theme parks and the Statue of Liberty.

Later this year, NCR plans to begin selling finger readers to stores for use by employees and customers who volunteer.