I am a Royal Society University Research Fellow in the Information Security Research Group of University College London, working on developing metrics for security and privacy. My research interests include authentication/passwords, banking security, anonymous communications, censorship resistance and covert channels. I have worked with the OpenNet Initiative, investigating Internet censorship, and for the Tor Project, on improving the security and usability of the Tor anonymity system. My current research on developing methods to understand complex system security is supported by the Royal Society. I am also working on analysing the security of banking systems, especially Chip & PIN/EMV, and am Innovation Security Architect of Cronto, an online authentication technology provider and part of the VASCO group. I am a Fellow of the IET and BCS.