Nationwide identity systems have been proposed as a solution for problems from counterterrorism to fraud detection to enabling electoral reforms. In the wake of September 11, 2001, and renewed interest in the topic, the Committee on Authentication Technologies and Their Privacy Implications of the Computer Science and Telecommunications Board developed this short report as part of its ongoing study process, in order to raise questions and catalyze a broader debate about such systems. The committee believes that serious and sustained analysis and discussion of the complex constellation of issues presented by nationwide identity systems are needed. Understanding the goals of such a system is a primary consideration. Indeed, before any decisions can be made about whether to attempt some kind of nationwide identity system, the question of what is being discussed (and why) must be answered.