The Swiss Federal Archives are obliged to archive Federal administration documents independent of the information medium. Therefore the problem of long-term archiving of relational databases must be resolved.

The SIARD Format has been used since 2007 by the Swiss Federal Archives and by many other archives around the world as a normalization format for the long-term preservation of relational databases

With SIARD Format 2.2 the databases are stored conforming to the standard SQL:2008 in order to guarantee long-term availability. Data content is stored as a collection of XML files. Because the resulting archive format is based on these two ISO standards, it is believed that lasting data comprehensibility is assured.

An important requirement of data content archived in SIARD format is that it should have "documentary character", i.e. the content of the archived tables should be comprehensible independently of any front-end processing applications and should represent the enterprise information of the institutions operating the subject databases. Neither executable code nor objects are archived by the SIARD Suite but only enterprise information from database tables. This is explained in more detail in the report "Long-term Preservation of Relational Databases, What needs to be preserved how?" by Hartwig Thomas.

The SIARD format stores the archived database schema definition in SQL:2008 conformant XML files while documentation in respect of the tables and fields, as well as the actual data, is also stored in XML files. In order to avoid excessive XML file size inflation, BLOBs and CLOBs (Binary Large OBjects and Character Large OBjects), referenced in the XML files, are stored in separate (binary) files.

This document does not further explain the SIARD format and structure as they are described in a separate document which was delivered together with the SIARD Suite. In 2013 the SIARD format was recognized as an eCH-Standard. In 2018 the version 2.1 of the SIARD format has been made available as standard eCH-0165.