In the guidelines on transparency, published on 28 November 2017, the WP29 points out that whilst transparency is not defined in the GDPR, the concept should be understood as user-centric rather than legalistic, and should therefore empower data subjects to exercise control over their personal data. Transparency is therefore intrinsically linked to fairness and the new principle of accountability, and requires the exercise of the practical requirements to have an adequate level of quality, accessibility and comprehensibility, but also accuracy of the actual content provided.

The guidelines discuss these requirements individually, and conclude by providing a schedule that stipulates what information must be provided to a data subject under Article 13 and 14 of the GDPR.