Prior consultation is the GDPR step where a controller asks a supervisory authority for advice before starting processing that still appears high risk after a Data Protection Impact Assessment (DPIA). It is not routine paperwork; it is a formal escalation when safeguards, minimization, and governance measures are not enough to reduce the danger to an acceptable level.
In cyber security, prior consultation matters because high-risk processing often involves sensitive personal data, vulnerable users, or complex third-party systems. If a service handles confidential contacts, health information, or safety-related records, an organization may need to justify its design choices before launch. Defenders use the process to prove that risks were reviewed, mitigations were considered, and residual risk was not ignored. Attackers indirectly benefit when organizations skip this step: weak approvals, poor vendor control, and untested incident handling can leave exposed data and brittle workflows. Prior consultation helps force those issues into the open before they become breaches.