The Federal Statistical Office does not keep its own residents' register and instead uses data from the federal residents' registers as well as those from the cantons and communes.
In order to carry out a register-based survey, the cantonal residents' registers, which are kept according to different rules in each canton, had to be harmonised or standardised. The register harmonisation project was set up to this effect. Register harmonisation is based on harmonisation guidelines, such as the Register Harmonisation Act (RHA, SR 431.02) and the Ordinance on Register Harmonisation (RHA SR 431.021). Since 2010 the project has become operational and the 2010 Population Census was a register-based one.
Henceforth the FSO receives data on residents for statistical purposes on a quarterly basis.
As part of the register harmonisation project, the sedex platform was also set up to allow designated authorities to send their residents' data safely and securely to the FSO. Today sedex is also open to users from outside register harmonisation or statistics.