The federal government’s use of new data technologies, specifically knowledge discovery in databases (KDD) applications, for counterterrorism purposes presents a serious challenge to existing constitutional privacy protections. The book explores whether this practice infringes upon constitutional privacy rights in general and the right to information privacy in particular. It includes a review of privacy scholarship as well as a broad discussion of how constitutional privacy has been conceptualized by the . Supreme Court and the . Circuit Courts of in three types of privacy cases: First Amendment anonymous speech and association cases, Fourth Amendment privacy cases, and cases involving the emerging information privacy doctrine