What is evil? Who does evil things? Who is evil? How do you know? Whether in response to witnessing mass suffering or feeling the sting of personal injustice, people confidently apply the "evil" label to perpetrators and the harm that they inflict, yet evil's essence remains mysterious to many. This book offers readers an accessible, social-scientific definition and analysis of evil in its various incarnations to foster a sophisticated and self-reflective understanding of the phenomenon, departing from ghoulish or self-righteous generalizations. Part 1 explores why most of us want to be seen as good, when and why we deem something evil, and what psychological and environmental factors increase our propensity for harming others in spite of our drive for social acceptance. Part 2 presents illustrative examples of how Part 1's insights can be applied, specifically examining hate, sadism, serial killers, group-based atrocities, organizational offenses, and familial abuse. The concluding chapter amplifies and integrates the book's big themes to foster a more mindful, informed confrontation of the elusive problem we call evil. Evil in Mind delivers a systematic, research-based psychological understanding of evil that is compact, digestible, and potentially transformative for academics, students, and educated lay readers.