One of the first countries in the world to introduce them, Sweden decided in 1947 to assign ID numbers to aid taxation, military service assignment, and census taking. Nowadays, citizens often get their personnummer right after birth, even before they have a name.
But there are privacy concerns about the possibility of profiling especially considering use of the number to make online transactions that might occur outside the country.
Simone Fisher-Hübner, a professor of computer sciences at Karlstad University, told Radio Sweden that a unique identifier was declared unconstitutional in her country of birth, Germany.
"In general there's a privacy principle that you should try to minimize the amount of personal data that you hand out. The issue with the personal number is that already it contains some details, your birth date and your gender. But if you frequently hand out data together with your personal number then all the data items that you've been handing out can be combined and profiled. So everything can be linked together, and more and more is known about you," said Fisher-Hübner.
In this edition of Radio Sweden Weekly we look at the use of the Swedish personnummer. We talk to Swedes about their relationship to the ten digit number, but also to people who have come here and tried to get one.