This book would not have been possible without the numerous co-authors and colleagues who have worked with us and commented on our research on taxes and inequality over the years, and without the support of our home institution, UC Berkeley. We want to thank in particular Heather Boushey, Lucas Chancel, Kimberly Clausing, Camille Landais, Claire Montialoux, and Thomas Piketty for their detailed comments on the manuscript. We thank our research assistants Akcan Balkir, Katie Donnelly Moran, and Clancy Green, and our agent Raphael Sagalyn. Special thanks to our editor Brendan Curry and his W. W. Norton colleagues for their invaluable work.