SURPRISE re-examines the relationship between security and privacy, which is commonly positioned as a ‘trade-off’. Where security solutions involve the collection of information about citizens, questions arise as to whether their privacy has been infringed. This infringement of individual privacy is sometimes seen as an acceptable cost of enhanced security. Similarly, citizens are seen as willing to trade-off their privacy for enhanced personal security in different settings. These common understandings of the security-privacy relationship, both at state and citizen levels, have informed policymakers, legislative developments and best practice guidelines concerning security developments across the EU. However, an emergent body of work questions the validity of the security-privacy trade-off, suggesting that this has over-simplified the consideration of the impact and acceptability of security solutions on citizens in current security policy and practice. Thus, the more complex issues underlying privacy concerns and public scepticism towards surveillance-oriented security solutions (SOSSs) may not be apparent to legal and technological experts. In response to these developments, this project will consult with citizens from several EU member and associated states on the question of the security-privacy trade-off as they evaluate different security solutions. Through extensive preparatory work, the project will identify and empirically examine the influence of a broad range of issues upon their evaluations. Using citizen consultation meetings, questionnaires and innovative visual methods, a representative, fine-grained picture from across Europe will be provided. Further, citizens’ understanding of privacy protection laws, their enforcement, and the acceptance levels of SOSSs, will be explained. Finally, a set of context-dependent dimensions for decision support concerning the acceptability of new SOSSs which promotes civil rights protection will be produced.