It will, we are promised, keep the unwanted and dangerous outside our borders, while streamlining entry for those welcome to come and visit.
But as the implementation of the scheme gets underway it is becoming clear that there could be serious problems with it.
With the old passport, we knew where we stood. If you lost it you knew you had lost it, but with the new, machine readable passports the story is very different.
When you take a digital photo the image is, in effect, a code, which means that however many prints you make they are all exactly the same.