Digital networks shape traditional actors (authors, readers, librarians, publishers, and other intermediaries), institutions (libraries, bookstores), processes (collaborative writing, translation, correction), and texts (hypertext, open access, wiki technology). The article deals with the main transformations in these fields from a media ecology perspective. Media Ecology is a discipline first outlined in the early 1960s by researchers like Marshall McLuhan, Neil Postman, and Walter Ong. From this perspective, the emergence of the World Wide Web in the 1990s and social media in the 2000s radically changed the conditions of the media ecosystem. In this new context the old media and actors must adapt to the new environment if they want to survive. The chapter deals with these mutations and adaptations in the specific field of book publishing.