In the presently heightened security environment in the United Kingdom there are a number of examples of policy that must strike a delicate balance between strengthening security and endangering civil liberties and personal privacy. The introduction of national identity cards and biometric passports, expansion of the National DNA Database and inter-departmental sharing of personal information raise a number of privacy issues. Human rights may also be suspended by the exercise of stop-and-search powers by the police or the detention of suspects prior to trial. However, much of the current debate concerning civil liberties and security is adversarial, and little robust research data informs arguments on both sides. This paper outlines the results of a study that attempts to objectively understand the real privacy, liberty and security trade-offs made by individuals, so that policymakers can be better informed about the preferences of individuals with regard to these important issues.