What are the limits of confidentiality?

With a few exceptions I don't repeat anything you say. The exceptions are:

a) I discuss my work with my clinical supervisor, and that is also a confidential relationship.

b) If a child is being abused, or is in danger of being abused this should be reported.

c) The Prevention of Terrorism act requires practitioners to give the police or security services any relevant information.

I comply with and am registered with the new  General Data Protection Registration (GDPR)  regulations and this forms a part of my contracting with clients.