This introduction presents an overview of the key concepts discussed in the subsequent chapters of this book. The book starts from the understanding that security is unbound, that insecurities are rendered as multiple and, through often banal, non-intense dispersing. It gives introduction to security that foregrounds political dimensions of security practice. Warnings about democracy being threatened by the political and security policies that claim to protect democracy against its enemies have been central to the political and judicial contestation of counter-terrorism policies. The book explores look in particular at surveillance combined with risk governance as a technological mode of connecting insecurities and governing social and political relations by means of suspicion. It deals with the question of how the technological nature of assembling suspicion limits the possibilities for democratic politics. Technology and the prioritising of technical and professional expertise are often perceived as de-democratising.