This chapter suggests that self-deception evolved to facilitate interpersonal deception by allowing people to avoid the cues of conscious deception that might reveal deceptive intent. Self-deception also eliminates the costly cognitive load that is typically associated with deceiving, and can minimize retribution if the deception is discovered. Beyond its role in specific acts of deception, self-deceptive self-enhancement also allows people to display more confidence than is warranted, which has a host of social advantages. Self-deception manifests itself in a number of different psychological processes, and this chapter reviews various types of self-deception. Finally, the chapter provides a brief review of recent research on self-deceptio...