Rome was second only to Venice as a center of sixteenth-century music book production on the Italian Peninsula. This book presents a broad view of music, print, and culture in the Eternal City from the origins of music printing in the late fifteenth century up through the early seventeenth century. It argues that economic and political factors encouraged Romans to become “boutique” printers, who, unlike their northern counterparts, customized their music publications to accommodate the requirements of a diverse clientele. Emphasizing the exceptionalism of these editions, the book highlights the innovative technologies, book forms, and mis-en-page utilized in the Caput Mundi, which included large folio and broadsheet formats, copperplate engraving, choirbook and open-score layout, as well as lute and keyboard intabulations. It considers the Church’s influence on the book industry and, in turn, the impact the Roman press had on such figures as Palestrina, Marenzio, Victoria, and Cavalieri. It reveals a synergistic relationship between music repertories and the materiality of the book, particularly during the post-Tridentine period, when repertories, both old and new, challenged printers to devise alternative printing methods and modes of book presentation in the creation of music editions, often of singular beauty as visual as well as musical objects.