Capability-Based Conformance

Unlike the 2015 edition's hierarchical model (Core → Extended → Hierarchical), the 2025 edition uses capability-based conformance:

  • Each register type provides specific capabilities
  • You claim conformance to the type(s) you implement
  • Types can be combined based on needs
  • There's no "highest" level—just the right fit

The Five Register Types

1

Content Register

Basic register with content management

Capabilities

  • Store and retrieve register items
  • Assign and manage identifiers
  • Track basic status (valid/invalid, published/unpublished)
  • Support required actions (add, invalidate, supersede)

Best For

Simple code lists, reference data, and lookup tables where governance is minimal and content doesn't change frequently.

Example: A country codes register with ISO 3166 alpha-2 codes.
2

Concept Register

Content + concept plane modeling

Capabilities (extends Content)

  • Model concepts and concept versions
  • Link register items to concepts
  • Track concept definitions and their evolution
  • Support concept relations (specialization, etc.)

Best For

Registers where the meaning of items matters as much as the data, or where definitions evolve over time.

Example: A scientific terminology register where definitions are refined as understanding improves.
3

Governed Content Register

Content + formal governance

Capabilities (extends Content)

  • Formal proposal and approval workflows
  • Role-based access control
  • Audit trails for all changes
  • Appeal process for disputed decisions

Best For

Registers that require accountability, transparency, or regulatory compliance—where you need to prove who approved what and when.

Example: A regulatory code list that must demonstrate compliance with governance requirements.
4

Governed Concept Register

Concept + governance capabilities

Capabilities (extends Concept)

  • All Concept Register capabilities
  • Formal governance for concepts and content
  • Approval workflows for concept changes
  • Concept-level audit trails

Best For

Enterprise terminology or taxonomy management where both meaning and content require formal governance.

Example: An enterprise data dictionary with governed business term definitions.

Choosing a Register Type

Use this decision tree to select the right type:

Do you need to track concept definitions separately from content?
Yes→ You need Concept capability
No→ Content capability is sufficient
Do you need formal governance (proposals, approvals, appeals)?
Yes→ You need Governance capability
No→ Basic management is sufficient
Will external users rely on this register as a definitive source?
Yes→ Consider CCR for full commitments
No→ Lower commitment levels are fine

Quick Selection Table

Use CaseRecommended TypeRationale
Internal code listContent RegisterSimple needs, no external users
Product taxonomyConcept RegisterDefinitions matter, governance optional
Regulatory compliance dataGoverned Content RegisterAudit trail critical
Enterprise data governanceGoverned Concept RegisterBoth meaning and process matter
National/international standardCCRFull trust and persistence required

Can I Mix Types?

The capability model is designed to be combinable:

  • Yes: You can implement capabilities from multiple types if your use case requires it
  • Claim carefully: Only claim conformance to types whose full capability set you implement
  • Document deviations: If you implement partial capabilities, document what's included and excluded
Note: While capabilities can be combined, the five types represent tested patterns. Deviating from them may increase complexity and reduce interoperability.

Conformance Testing

How do you verify conformance when requirements are capability-based?

Testing Approach

  1. Identify claimed type(s): What conformance class(es) does your register claim?
  2. Map to capabilities: Each type has required capabilities
  3. Test each capability: Verify the capability is implemented and functional
  4. Document evidence: Provide examples, screenshots, or API demonstrations

Self-Assessment Checklist

Content Register

  • ☐ Can add new register items
  • ☐ Can assign unique identifiers
  • ☐ Can invalidate items
  • ☐ Can supersede items
  • ☐ Can track valid/invalid status
  • ☐ Can track published/unpublished status

Concept Register

  • ☐ Can define concepts
  • ☐ Can version concept definitions
  • ☐ Can link items to concepts
  • ☐ Can define concept relations

Governance

  • ☐ Can submit proposals
  • ☐ Can review and approve/reject proposals
  • ☐ Can assign roles
  • ☐ Can appeal decisions
  • ☐ Maintains audit trail

Related Topics

  • Getting Started - Begin implementing your register
  • Commitments - Understanding access, persistence, and transparency
  • Samples - Complete register specification examples