Surveys have repeatedly identified privacy as one of the most pressing concerns of those using new information technology. Only in terms of Internet sales, billions of dollars are said to be lost every year because of privacy fears. At the same time, academic research and security industry efforts have developed protocols and technologies to protect individuals' privacy in almost any conceivable scenario— from browsing the Internet to purchasing on- and off-line. There is a demand, and there is an offer. So, why is there no market clearing?