This system is responsible for identifying taxpayers towards the Tax and Customs Authority, acting as an important security mechanism in the access of information and services provided digitally. It is a system that offers several accreditation alternatives, including VAT number and tax portal’s password, the Citizen’s Card or EORI (Economic Operator Registration and Information System), and the access to services is managed according to each taxpayer’s profile and authorisation level. The system is currently used by several Public Administration entities, as a way to ensure the identification and correct access of citizens to services.