Human factors and usability issues have traditionally played a limited role in security research and secure systems development. Security experts have largely ignored usability issues - both because they often failed to recognize the importance of human factors and because they lacked the expertise to address them. But, there is a growing recognition that today's security problems can be solved only by addressing issues of usability and human factors. Increasingly, well-publicized security breaches are attributed to human errors that might have been prevented through more usable software. Indeed, the world's future cyber-security depends upon the deployment of security technology that can be broadly used by untrained computer users. Still, many people believe there is an inherent trade-off between computer security and usability. It's true that a computer without passwords is usable, but not very secure. A computer that makes you authenticate every five minutes with a password and a fresh drop of blood might be very secure, but nobody would use it. Clearly, people need computers, and if they can't use one that's secure, they'll use one that isn't. Unfortunately, unsecured systems aren't usable for long, either. They get hacked, compromised, and otherwise rendered useless. There is increasing agreement that we need to design secure systems that people can actually use, but less agreement about how to reach this goal. ""Security undefined Authentication Mechanisms - techniques for identifying and authenticating computer users; Secure Systems - how system software can deliver or destroy a secure user experience; Privacy and Anonymity Systems - methods for allowing people to control the release of personal information; Commercializing Usability: the vendor perspective - specific experiences of security and software vendors (e.g., IBM, Microsoft, Lotus, Firefox, and Zone Labs) in addressing usability; and The Classics - groundbreaking papers that sparked the field of security and usability. This book is expected to start an avalanche of discussion, new ideas, and further advances in this important field.