I would like to thank Rachael Comunale and Kristine Haglund for their help and advice throughout this project and Nancy Toff, at Oxford University Press, for suggesting the topic in the first place. I appreciate the support of Harvard Business School, especially that of Dean Nitin Nohria, the Division of Research and Faculty Development, and Baker Library. I would also like to thank those who made suggestions along the way, including Sven Beckert, Leslie Berlin, Brian Cheffins, James Cortada, Peter Eisenstadt, Jeanette Estruth, David Frankel, Robert Fredona, Marc and Danielle Green, Per Hansen, Richard R. John, Ana Kolendo, Laura Linard, David Moss, Tom Nicholas, Rowena Olegario, Natasha Overmeyer, Susie Pak, Larry Perlov, Jennifer Quick, Sophus Reinert, Christine Riggle, Laura Phillips Sawyer, Nitzan Shear, Jonathan Silvers, Jeff Strabone, Richard Tedlow, Charles Wilson, Mark Wilson, and Robert Wright. I am especially grateful to my family, Susan Burgin and Orli Friedman.