Double taxation occurs when two countries simultaneously tax the same person on the same income or assets. Double taxation agreements (DTAs) prevent double taxation and facilitate cross-border economic transactions. DTAs also regulate the exchange of information upon request in tax matters. Switzerland has been applying the OECD standard in full since 2009. The standard has also allowed group requests since 2012.
Switzerland has also signed tax information exchange agreements (TIEAs), which, unlike DTAs, are concerned solely with the exchange of information upon request.