Developing an interoperability framework requires a multi-stakeholder process and a long-term vision for the ID system. As per the European
Interoperability Framework, there are four interoperability layers that need to be defined:

Legal interoperability
Legal, policy, and regulatory frameworks define the scope of interoperability, particularly with regard to data exchange and requirements for privacy and data protection.

Organizational interoperability
For interorganizational-interoperability, federation, or mutual recognition of ID systems, organizations must define trust frameworks and process standards around the identity lifecycle (e.g., the eIDAS standards).

Semantic interoperability
To ensure that the meaning of exchanged data and information is consistent, systems must adopt the same data standards or construct data dictionaries.

Technical interoperability
To enable machine-to-machine communication, systems must adopt the same technology standards for software, physical hardware components, and systems and platforms.

Throughout these four layers, interoperability frameworks also rely on crosscutting integrated public service governance to ensure usability, security, privacy, and performance.