This Practice Note covers the principles for handling personal data that form the core of the United Kingdom General Data Protection Regulation, Assimilated Regulation (EU) 2016/679 (UK GDPR), and which are set out in Article 5 of the UK GDPR regime. The principles include: the lawfulness, fairness and transparency principle, the purpose limitation principle, the data minimisation principle, the accuracy principle, the storage limitation principle, the integrity and confidentiality principle (which relates to data security) and the accountability principle.