Questions of symbolic classification have been central to sociology since its earliest days, given the relevance of distinctions for both affiliation and conflict. Music and its genres are no exception, organizing people and songs within a system of symbolic classification. Numerous studies chronicle the history of specific genres of music, but none document recurrent processes of development and change across musics. In this article, we analyze 60 musics in the United States, delineating between 12 social, organizational, and symbolic attributes. We find four distinct genre types—Avant-garde, Scene-based, Industry-based, and Traditionalist. We also find that these genre types combine to form three distinct trajectories. Two-thirds originate in an Avant-garde genre, and the rest originate as a scene or, to our surprise, in an Industry-based genre. We conclude by discussing a number of questions raised by our findings, including the implications for understanding symbolic classification in fields other than music.