NGO administrators determine who can use the address book feature. For this, you can determine which tag people will benefit from this feature from the Users&Companies / Tags menu.
People who want to take part in the address book should log in to their accounts and turn off the Hide My Profile option from the Privacy & Settings tab in the My Information menu. By default, all contacts' information is hidden.
Your institution decides which fields of personal information will be included in the index and the title of Data Supervisor specified in the GDPR.
You can edit whether these fields are included in the index field or not from the details of the person information fields in the Users&Companies / User Defined Fields menu.