This book investigates the science behind "big liars"--those rare people who use lies as their principal way of navigating life. Most people are mostly honest, most of the time. And there aren't that many big, pants-on-fire liars in the population overall. But just a few big liars can have an outsized impact on the people around them--ruining personal relationships, bankrupting businesses, and even, when they attain political power, undermining the fabric of society. Big Liars explores this small but dangerous group through the lens of psychological science. Fascinating new research gives us insight into the nature of dishonesty and dishonest people, explaining who lies, what types of people lie a lot, how often people lie, how big liars are created, how they operate, how we can recognize them, and how we can avoid being victimized by them. This book has crucial implications for mental health treatment, as well as our efforts to grapple with the effects of big liars--and their big lies--on social movements and society as a whole.