Germany has become the first European Union country to introduce biometric passports.
By Abby Darcy
BBC News, Berlin
The new German passport contains a microchip in the cover
The new passport looks much like the old one, but airport control devices can detect a minute electronic tag concealed inside the cover.
German Interior Minister Otto Schily described the new e-passport as "a real security bonus".
He said the new technology would make forgery "impossible - or at least more difficult". Critics say that is not good enough.
The new biometric passport contains a paper-thin computer chip. Stored on this chip is a scan of the holder's face.
After 2007 the chip will also include fingerprint scans and iris scans could follow later.
When passengers have their passports checked at the airport, a device will scan their face whilst the immigration officer swipes the passport past another control device to check whether the information matches.
But security tests carried out on the new e-passport have left many questions unanswered, says the data protection commissioner, Peter Schaar. He wanted more transparent testing before the passports were introduced.
"The authorities gave us virtually no information about the results of the security testing that was done," he says. "We haven't been able to properly assess how secure the new passport will be."
Mr Schaar's main concern is unauthorised access to the confidential biometric data. He wants to see more safeguards.
The German government has ruled out a centralised database of the confidential information. "But who says this won't happen abroad?" he says. "We need an EU-wide ruling to prevent storage of this data. This has all happened too fast."
And Mr Schaar insists there is no need to rush.
Germany is introducing the new biometric passport well ahead of the rest of Europe. The European Union requires its member states to begin issuing biometric passports by August 2006.
The UK passport service aims to start from February next year.
The pressure came from the US after the terror attacks on 11 September 2001.
Hamburg was the meeting place for the key hijackers involved in the attacks on New York and Washington, including their leader Mohammed Atta, investigators say.
Only travellers with a biometric passport can continue to enter the US without a visa - after October 2006.
But the German government is not shy about why Germans should be the first to have an e-passport in their pocket.
If successful, the new technology will boost Germany's image abroad and benefit the semiconductor industry.
The biometrics market is still in its infancy. So German companies like Infineon, who produce microchips for the new e-passport, could have a profound impact on this market.
Applying for a new passport will now cost double what it used to.
One Berliner, Werner Kirchgaesser, said it was not worth the extra money. "This is the wrong solution," he said. "I don't believe this can help fight terrorism. Although I know we need to be tougher."
His scepticism was echoed by Alexander Katzenberger.
"The politicians aren't sure what to do. But they want to do something," he said. "I don't like the idea. It's just a meaningless gesture."
It is only the beginning, according to a Christian Democrat MP, Clemens Binninger. "We're on the right path," he said.
"But the future lies in combining the biometric data with CCTV. We saw how vital cameras were in identifying the terrorists responsible for the attacks in London."
Another Berliner was philosophical about the new passport. "I lived through the communist GDR," she says. "Privacy wasn't much of a priority then either."