In Acuna, evidence records follow four states: Draft (being compiled), Submitted (sent for approval), Approved (locked and timestamped), and Expired (no longer current). Each record captures collection, review, and expiry dates, supports versioned file attachments, and can be linked to multiple controls with per-link notes. Approvers receive notifications and can request changes before accepting. Approved evidence contributes to control effectiveness and audit readiness metrics. Expired evidence is flagged visually and cannot be deleted without administrator approval, preserving the audit trail.