The Experimental Book Object shows why and how books matter in the 21st century. Digital and audio platforms are commonplace, and other fields of art beyond literature have increasingly embraced books and publication as their medium of choice. Nevertheless, the manifold book object persists and continues to inspire various types of experimentation. This volume sets forth an unprecedented approach where literary and media theory are entangled with design practitioners' artistic research and process descriptions. By probing the paradigm of the codex, this collection of essays focuses on historical and contemporary experimentation that has challenged what books are and could be from the perspectives of materiality, mediation, and visual and typographic design. Investigations into less-studied areas and cases of performativity demonstrate what experimental books do by interacting with their systemic and cultural environments. The volume offers a multifaceted and multidisciplinary view of the book object, the book design and publishing processes, and their significance in the digital age.