This casebook provides a coherent treatment of the major issues arising in terrorism investigations and prosecutions. It highlights differences in the criminal law and procedure rules applied in civilian terrorism cases with those used in ordinary crime matters and military commission processes. This edition has been thoroughly revised and reorganized to include the latest cases, statutes, and administrative materials regarding proactive surveillance, FBI interrogation rules, national security letters, and military detention and interrogation. It includes, inter alia, extended notes on changes effected by the Obama administration and issues arising out of the effort to close Guantanamo.