Terrorism presents a greater threat to national and transnational security today than it has presented at any time in history. Better technology, communications, weapons, and modes of transportation are at terrorists' disposal. Many terrorism cases will be proven in court through forensic evidence, so it is important that extensive crime scene investigations be conducted. The types of terrorism include left- and right-wing extremism, religious, single-issue, and cyber terrorism. Every investigative technique used to solve criminal cases can be used with terrorist investigations. Terrorists are unlikely to cooperate with authorities after being arrested. They study law enforcement operations and alert colleagues on investigation techniques. The interview is the most common investigative technique that an officer will use. Straightforward questions or devious tactics can both be used to gather information during the interview. Terrorists are usually reluctant to submit to interviews with law enforcement officers. Record checks are usually the easiest investigative technique available to an investigator. Surveillance is a valuable investigative tool because it involves actual observations that are useful in affidavits and obtaining arrest warrants. Informants who can provide the most valuable information are likely to be from the inside. Investigators often overlook someone on the periphery to a conspiracy but they can provide tips and leads. Trash cover is an investigative technique that involves law enforcement recovery of discarded materials. A pretext telephone call is a covert investigative technique in which the caller tries to elicit information without telling the recipient that the calls is associated with police. Physical evidence plays an important role in most criminal cases and plays an even more significant role in terrorism cases as it can be used to develop a case without an expert examination. A crime scene is terribly important, as evidence obtained from a crime scene is difficult for a subject to dispute in court. An investigative task force helps track terrorists as they move about the country. Undercover operations may mean a one-time contact or it could mean frequent contacts, but concerns include whether the agency will be able to provide support and will the undercover agent be recognized? Microphones or wire taps, closed-circuit television, and tracking devices are some examples of surveillance equipment. An investigative review is useful in long cases when someone reviews the entire case and can spot weaknesses. Underground terrorists appear to live a normal life but have false identities; they will abandon friends and families who do not share their views and they usually have a support network. The book also provides guidance for factors to be considered when implementing investigative techniques, such as what can happen in court, ethical issues with investigative techniques, and uses and types of covert locations. The book also provides guidance on what to do when a clandestine terrorist is identified and when a terrorist incident occurs. Appendices, index