# CII

UN/CEFACT Cross Industry Invoice: an XML syntax used for e-invoices.

## Definition

UN/CEFACT Cross Industry Invoice: an XML syntax used for e-invoices.

## Explanation

Forms the XML basis for ZUGFeRD/Factur-X profiles.

Alternative to UBL for EN 16931 implementations.

## Related resources

- [CII guide](/resources/compliance/cii-cross-industry-invoice)

## Related terms

- [ZUGFeRD](/resources/glossary/zugferd): Hybrid e-invoice format: a human-readable PDF with embedded XML.
- [Factur-X](/resources/glossary/factur-x): French hybrid e-invoice format, aligned with ZUGFeRD and EN 16931 profiles.
- [EN 16931](/resources/glossary/en-16931): European standard defining the semantic data model for e-invoices.
- [UBL](/resources/glossary/ubl): Universal Business Language: an XML library for standard business documents.