> For the complete documentation index, see [llms.txt](https://frameworks.greendealdata.eu/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://frameworks.greendealdata.eu/governnace-frameworks/gdds-rulebook/data-sovereignty-and-technical-governance/2.-semantic-transparency-and-interoperability.md).

# 2. Semantic transparency and interoperability

## Rule&#x20;

Participants are required to declare the data models, vocabularies, code lists, or classifications used in their data offerings, together with references to their authoritative definitions. This obligation of semantic transparency enables other participants, intermediaries, and value-added service providers to assess semantic compatibility and build cross-domain applications without ambiguity.&#x20;

### Procedure&#x20;

GDDS does not impose a single, uniform data model across all domains. Instead, it adopts a federated and layered semantic approach that encourages reuse of existing, recognised standards where mature and adopted, while permitting participants to use domain-specific or local models where no widely adopted standard exists, provided these are clearly documented, versioned, and referenced in the metadata of the published data product.  &#x20;

The GDDS supports an incremental model of semantic integration, reducing initial barriers to entry while enabling participants to raise their semantic interoperability maturity over time. This reflects the diversity of the initial 10 GDDS use cases and avoids creating disproportionate barriers to participation.&#x20;

## Responsible body&#x20;

Each participant is responsible for declaring and documenting the semantics of its own offerings. The DSGA is suggested to maintain oversight of accepted data models and vocabularies and ensures cross-domain alignment where necessary. The supported levels of semantic abstraction and the technical specifications are described in the Technical Framework (see [Data Interoperability — Data Models)](/11-data-interoperability/data-models.md).&#x20;