Recital 82
Recital 82 of the GDPR, as in force since 25 May 2018. Its key is gdpr-recitals:rec-82.
In order to demonstrate compliance with this Regulation, the controller or processor should maintain records of processing activities under its responsibility. Each controller and processor should be obliged to cooperate with the supervisory authority and make those records, on request, available to it, so that it might serve for monitoring those processing operations.