Despite being one of the biggest industries in the world, the "dream factory" that is Hollywood is little understood outside the business. The Hollywood Studio System fills that gap. It is the first book to describe and analyze the complete development, operation, and reinvention of the global corporate entities that produce and distribute most of the films we watch. Starting in 1920, Adolph Zukor, head of Paramount Pictures, helped to fashion Hollywood into a vertically integrated system, a set of economic innovations that was firmly in place by 1930. For the next three decades, the movie industry operated according to these principles. Cultural, social, and economic changes ensured the demise of this system after WWII. Beginning in 1962, Lew Wasserman of Universal Studios emerged as the key innovator in creating a second studio system. Gomery relates the history of these two systems using primary materials from a score of archives across the United States as well as a close reading of both the business and trade press of the time. A number of previously unpublished photos illuminate the narrative.