# Pseudonymisation · Glossary
Replacing direct identifiers such as names or account numbers with artificial keys, while keeping the information needed to re-identify individuals separately and under additional controls.
[Glossary](/glossary) · Data privacy and security

# Pseudonymisation

     Replacing direct identifiers such as names or account numbers with artificial keys, while keeping the information needed to re-identify individuals separately and under additional controls. Under UK GDPR, pseudonymised data is still personal data.

## Why it matters

     Pseudonymisation lets analysts and data scientists work with individual-level records without seeing who the individuals are. It reduces the impact of a breach and supports role-based access, because only a small group can hold the re-identification key.

     It is a risk-reduction measure, not an exemption. Organisations still need a lawful basis, security controls and a DPIA where appropriate, and should test whether combinations of remaining fields could identify people.

## In practice

     For example, a UK clinical research team might replace patient identifiers with study IDs before loading records into its analytics environment. The mapping table sits in a separate, tightly controlled store used only when a clinician needs to follow up an individual result.

## Where Rodan fits

     Rodan builds pseudonymisation into analytics and AI pipelines delivered through [Data and Analytics Engineering](https://rodan.io/data-analytics-engineering), with key management and access separated from the analytical environment.

## Related terms

- [Anonymisation](/glossary/anonymisation)

- [Personally identifiable information (PII)](/glossary/personally-identifiable-information)

- [Encryption](/glossary#encryption)

- [Synthetic data](/glossary#synthetic-data)

- [Data minimisation](/glossary/data-minimisation)
HTML: https://rodan.io/glossary/pseudonymisation