Evil is ubiquitous. But why does it exist, why is it so pervasive, and how should we think about and respond to it? In a rigorous but lively way, Evil: A Guide for the Perplexed explores these questions and much more, and it does so from both theistic and non-theistic perspectives, from both the East and the West. It examines traditional philosophical and theological problems raised by the existence of widespread evil, and it also engages with more recent ones, from new challenges posed by scientific advances in evolutionary theory, neuroscience, and cosmology, to concerns of climate change and environmental degradation, to questions raised by increasing religious and secular violence. The overall goal is to provide a thoughtful, engaging, even-handed guide to examining both classical and contemporary issues raised by the reality and ubiquity of evil.