Whether U.S. terrorism-prevention efforts match the threat continues to be central in policy debate. Part of this debate is whether the United States needs a dedicated domestic counterterrorism intelligence agency. This book examines, from a variety of perspectives, the proposal that such an agency be created, including its possible capabilities, comparing its potential effectiveness with that of current efforts, and its acceptability to the public, as well as various balances and trade-offs involved in creating such an agency. The book's unifying message is one of caution and deliberation; there is a need to carefully consider the implications and potential outcomes of such significant policy changes.