Privacy Impact Assessment (PIA)
A procedure for analyzing and remediating personal-information risk before a system that handles personal data is built or changed.
I. Overview
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A["Building or changing\na system"] -- "analyzing and remediating\nrisk factors" --> B["Preventing personal\ninformation breaches"]
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Definition: A Privacy Impact Assessment (PIA) is an institutional procedure that analyzes personal-information risk factors and derives improvements whenever a system operating personal information files is built or changed.
Features:
( Privacy by Design ) Personal-information protection considerations are reflected in the design from the earliest stage of system development.
( Breach prevention ) Potential personal-information exposure risks are analyzed in advance to prevent breaches at the source.
( Legal safety ) Compliance with the Personal Information Protection Act and related legislation resolves legal risk and improves organizational trust.
II. Mechanism & Components
Mandatory Assessment Targets (for Public Agencies)
- Personal information files that include sensitive information or unique identification information on 50,000 or more data subjects.
- Personal information files that link and process personal information on 500,000 or more data subjects.
- Building or changing a personal information file covering 1,000,000 or more data subjects.
Step-by-Step Procedure
| Step | Key Activities | Key Deliverable |
|---|---|---|
| 1. Assessment Preparation | Select the assessment agency, form the assessment team, draft the assessment plan | Assessment contract, assessment plan |
| 2. Data Collection | Analyze data flow, understand system structure, conduct interviews | Personal information flow/mapping diagram |
| 3. Risk Analysis | Check compliance with personal-information protection principles, identify risk factors | Risk analysis report |
| 4. Developing Improvements | Establish measures to remove or mitigate identified risks | Improvement recommendations |
| 5. Reporting Results | Draft the assessment result report and submit it to the Ministry of the Interior and Safety / Personal Information Protection Commission | Assessment result report |
III. Adoption Considerations & Security Measures
| Risk Area | Primary Control |
|---|---|
| Collecting more personal information than the stated purpose requires | Minimum-collection principle, documented legal basis |
| Weak technical safeguards around stored personal information | DB encryption (API/TDE), access control, 2FA, retained access logs |
| Handlers without differentiated access or training | Internal management plan, regular training, role-based authority |
| Physical exposure of storage media or the server room | Locking devices, media control solutions, restricted room access |
Run the PIA before the system is built, not after — its entire value is catching a re-identification or over-collection risk while it’s still a design change instead of a production incident. Treat it as complementary to, not a substitute for, ISMS-P: a PIA clears one system at build time (Article 33), while ISMS-P verifies the whole management system keeps operating correctly year over year, and organizations that only do one end up blind to the other’s failure mode.
Last updated 18 Aug 2026, 00:00 UTC.