This is a vivid account of how some citizens actively assist state surveillance by 'informing' on others, such as during the Cold War and the current campaign against terrorism. With Snitch!, Steve Hewitt provides a thorough study of human informers, i.e., people who secretly supply information to a domestic security agency (a spy provides information to a foreign intelligence service.) The work begins with an examination of the rise of the modern security state through the Cold War to today's ongoing 'long war' on terror. Using a unique comparative approach, Hewitt analyzes the practical and political aspects of informing, drawing on past and present examples from the United States, United Kingdom, former Soviet Union, and other countries. He argues that although the scale of the use of informers by domestic security agencies differs from nation to nation, the nature of their use and the impact on those targeted by this form of surveillance do not. An engaging read that combines scholarly research and specific case studies, Snitch! will appeal to anyone interested in security and intelligence as well as in issues surrounding the use of informers, especially in democratic societies.