--- title: "Rationale \u0026 Classification" url: https://ott.earth/cdo/rationale-classification/ lead: "CDOs are the backbone of enterprise data strategy. They ensure every key business concept is defined, governed, and used — whether it's a regulatory code, a company-wide standard, or a project-specific object." author: "Pavel Ott" source: https://ott.earth/ license: CC BY 4.0 --- # Rationale & Classification > CDOs are the backbone of enterprise data strategy. They ensure every key business concept is defined, governed, and used — whether it's a regulatory code, a company-wide standard, or a project-specific object. CDOs fall into three classification tiers. **Architecture stability depends on a strong base of standardised CDOs** — the wider that base, the more resilient the enterprise.
Stable — wide base of standards
Bespoke Local · Controlled risk Enterprise Canonical Shared meaning across domains External Standard Industry · Regulatory · Interop
✓ grounded ✓ resilient ✓ scalable
Unstable — flipped pyramid
Bespoke Canonical
! top-heavy ! coupling risk ! drift

A healthy enterprise has a wide base of External Standard and Enterprise Canonical CDOs and a small, controlled set of Bespoke CDOs. If the pyramid flips — too many bespoke concepts at the top — architecture becomes unstable.

## How each tier works

External Standard

Industry / Regulatory
Who uses it?
All business units that must exchange data with partners, regulators or industry bodies.
Why it matters
Guarantees interoperability and compliance — the legal & technical safety net.
Key governance
Track source authority & version; never alter the definition — only map it internally.

Enterprise Canonical

Cross-domain
Who uses it?
Cross-domain teams (e.g., sales, finance, operations).
Why it matters
Provides a single, shared meaning for data that lives in multiple systems.
Key governance
Managed by the Data Governance Council; changes require an RFC and impact assessment.

Bespoke

Local Use
Who uses it?
Project or pilot teams where standardisation isn't feasible.
Why it matters
Allows rapid development while controlling the risk of accidental enterprise coupling.
Key governance
Label as "Bespoke", assign owner & expiry date, review quarterly, and provide a migration path if it becomes widely useful.
Architectural rule: if the pyramid flips — too many bespoke concepts at the top — architecture becomes unstable.