PSD2 is the EU Directive, which is the basis for introducing a single market for payments in the European Union. It sets new rules on the protection and security of payments and adopts a new type of payment service provider and new payment transactions. PSD2 is also intended to facilitate international payments within the EU and to make them better integrated.

PSD2 publishes a new directive containing regulations for a new set of services, exposed by the XS2A interface, to be operated by licensed Third Party Providers (TPPs) on behalf of a bank's customer, referenced as Payment Service User (PSU). Each of the three services exposed in the XS2A Interface can be operated by a TPP with a specific eIDAS certificate containing the roles linked to the services.