Our societies are becoming ever more digitised. The pace of technological developments and how personal data are being processed affects each of us every day and in all sorts of ways in the light of these changes. Legal frameworks of the European Union (EU) and the Council of Europe that safeguard the protection of privacy and personal data have recently been reviewed. Europe is at the forefront of data protection worldwide. The EU’s data protection standards are based on Council of Europe Convention 108, EU instruments – including the General Data Protection Regulation and the Data Protection Directive for Police and Criminal Justice Authorities – as well as on the respective case law of the European Court of Human Rights and of the Court of Justice of the European Union. The data protection reforms carried out by the EU and the Council of Europe are extensive and at times complex, with wide-ranging benefits and impact on individuals and businesses. This handbook aims to raise awareness and improve knowledge of data protection rules, especially among non-specialist legal practitioners who have to deal with data protection issues in their work. The handbook has been prepared by the EU Agency for Fundamental Rights (FRA), with the Council of Europe (together with the Registry of the European Court of Human Rights) and the European Data Protection Supervisor. It updates a 2014 edition and is part of a series of legal handbooks co-produced by FRA and the Council of Europe. We express our thanks to the data protection authorities of Belgium, Estonia, France, Georgia, Hungary, Ireland, Italy, Monaco, Switzerland and the United Kingdom for their helpful feedback on the draft version of the handbook. In addition, we express our appreciation to the European Commission’s Data Protection Unit and its International Data Flows and Protection Unit. We thank the Court of Justice of the European Union for the documentary support provided during the preparatory works of this handbook.