Privacy Impact Assessment

A Privacy Impact Assessment (PIA), known under GDPR as a Data Protection Impact Assessment (DPIA), is a structured process for evaluating the privacy risks of a project, system, or processing activity that involves personal data. It identifies potential privacy issues, assesses their impact on individuals, and recommends measures to mitigate those risks before the processing begins.

When a PIA Is Required

Under GDPR Article 35, a Data Protection Impact Assessment is mandatory when processing is likely to result in a high risk to individuals' rights and freedoms. Specific triggers include:

• Systematic and extensive profiling with significant effects on individuals
• Large-scale processing of special category data (health, biometric, genetic data)
• Systematic monitoring of publicly accessible areas
• New technologies that present novel privacy risks
• Automated decision-making that produces legal or similarly significant effects

What a PIA Contains

A comprehensive PIA typically includes:

• Description of processing — What data is collected, from whom, for what purpose, and how it flows
• Necessity and proportionality — Why the processing is needed and whether the data collected is proportionate to the purpose
• Risk assessment — Identification of risks to individuals' rights and freedoms
• Mitigation measures — Controls and safeguards to reduce identified risks
• Consultation — Input from the Data Protection Officer and, where appropriate, from data subjects

Why It Matters

Beyond GDPR compliance, PIAs are a practical tool for identifying privacy risks early — when they are cheapest to address. Discovering privacy issues after launch can require costly re-engineering, damage customer trust, and trigger regulatory scrutiny.

ISO 27001 supports privacy impact assessment through its risk management framework. Organizations implementing both ISO 27001 and GDPR can integrate PIAs into their existing risk assessment process.

HIPAA does not use the PIA terminology, but the Security Rule's requirement for risk analysis serves a similar function for protected health information.

Best Practices

Conduct PIAs early. Perform assessments during the design phase of new systems or processes, not after they are built. Privacy by design is a GDPR principle and a practical cost-saver.

Document your methodology. A repeatable, documented PIA process ensures consistency and demonstrates compliance to regulators.