# Data Minimization and Purpose Limitation
One-sentence definition: Collect and process only the minimum data necessary for a stated purpose.
## Key Facts
- Reduces breach impact and compliance burden.
- Requires purpose documentation and periodic review.
- Supports privacy by design/default in systems.
- Use aggregation, masking, and deletion workflows.
- Align access roles with actual need-to-know.
- **Verify:** check official (ISC)² CBK and current exam outline.
## Exam Relevance
- Choose design that enforces least data collection/retention.
**Mnemonic:** “Less data, less risk.”
## Mini Scenario
Q: App requests date of birth when only age bucket needed—fix?
A: Collect only bucket; update forms and API.
## Revision Checklist
- Define minimization and purpose limitation.
- Give two technical enforcement examples.
- Link to risk reduction.
## Related
[[Privacy Principles and Data Protection]] · [[Data Classification Levels and Handling Rules]] · [[Pseudonymization vs Anonymization]] · [[Tokenization]] · [[Access Control to Data Assets]] · [[Domain 2 - Index]]