This book is a product of three decades of studying and working at screenwriting as my primary vocation, including the better part of a decade teaching the craft at institutions like UCLA Extension and National University and as a mentor to hundreds of writers of various levels, around the world. In working with them, I began to codify a body of knowledge, opinion, and advice that led to the principles outlined in this book. And so I’m indebted first and foremost to all of those writers who came to me for guidance and feedback and trusted me with their work. Colleagues in my teaching and writing careers have also helped me tremendously, especially Tom Hanks, who gave me my start as a professional writer and employed me on project after project, with all the charm, intelligence, passion, and easygoing generosity you would expect from him. The amazing producer Tony To helped me make good on those opportunities on the miniseries Band of Brothers and From the Earth to the Moon, the projects for which I am still best known. I also have to thank Brett Loncar, my longtime television packaging agent at CAA, who was a key figure in helping me to understand what makes a viable premise in TV—mostly by shooting down so many that weren’t, but also by advocating passionately for those that were. Finally my wife, Margaret, an immensely talented singer, songwriter, and creator of musicals, has supported me and been my biggest cheerleader as I develop my own projects and help others to do the same.