These slides were presented during the KT4D webinar "Navigating Research Ethics and Managing Sensitive Data in Complex European Projects" on 29 February 2024. This webinar seeked to open a discussion about the challenges of following research ethics best practices under these conditions, and deal tin particular with data protection and pseudonymisation.  Pseudonymisation is a data processing operation that allows personal data to no longer be attributed to a specific individual without the use of additional information. Two highly skilled experts in this area - Alberto Bettiol and Kate Francis of KT4D Partner organisation ICT Legal Consulting - concretely demonstrated what KT4D is doing in practice for our Use Cases. Jennifer Edmond, KT4D coordinator, moderated the event.