For over half a century researchers have scientifically studied persuasion and influence. The corpus of this research resulted in established theories and practices that are effectively used in a myriad of contexts where human relationships and factors are paramount. This chapter first explores traditional psychological influence concepts and techniques that are implemented across a broad spectrum of contexts, such as business, advertising, and political and military campaigns. The chapter then examines these principles through the lens of cyber attacks,where these precepts can be maliciously leveraged by cyber attackers to manipulate victims through elaborate deception narratives based upon exploiting heuristic cues to persuade and gain compliance. Finally the chapter looks at hoax viruses, scareware, “tech support scams,” and ransomware campaigns and the manner in which psychological influence strategies are weaponized in these attacks.