The document discusses the Spanish Tax Agency's perspective on the new VAT legislative framework for electronic invoices. It outlines how the Tax Agency has been accepting digitally signed tax returns and invoices from suppliers since 1998. It also details how the Tax Agency works with other groups to define standards like an XML format for electronic invoices. Both parties in a transaction need proof of authenticity, integrity, and legibility of electronic invoices according to the new regulations. Electronic invoices must be stored in a way that ensures the conditions for authenticity of origin and integrity of content.