From the pathological killer who gunned down the innocents at Virginia Tech to the average citizen who suspects the government is monitoring phone calls, the signs of suspiciousness and paranoia are all around us. In this comprehensive overview of an increasingly serious problem, an experienced psychologist and researcher describes what paranoia is, how and why it manifests itself, and the many forms it takes, including stalking, pathological jealousy, as a reaction to post-traumatic stress disorder, and perhaps even militia movements. Using striking vignettes from the present and the past, each chapter illustrates specific manifestations of paranoia while also describing in layperson’s terms the clinical analysis of the condition. Among the topics are delusional paranoia, paranoid symptoms in the elderly, the evolutionary origins of our suspiciousness system and factors that can trigger it today, the connection between illicit drug usage and paranoid behavior, jealousy, PTSD, violent reactions to paranoia, and the treatments available. The author emphasizes that life in contemporary America is a fertile environment for paranoia; in an era of computer hackers, omnipresent sec