Artistic authorship is fundamental to how we both interpret and value artworks. The figure of the solitary, creative genius underpins the symbolic and monetary values we ascribe to artworks; yet artistic authorship, like ownership, is often contested and unstable. This interdisciplinary collection of essays, written from legal, art historical, and art market perspectives, critically examines the construction and iteration of the artist-author both during the lifetime of the artist and beyond—when artistic authorship is stewarded by others, including artists’ estates, foundations, and museums. Drawing on current cases and legal disputes, this important anthology addresses enduring issues that have become central to the contemporary art world, such as the collision between artists’ rights and the rights of the owners of artworks, the problems of authentication and who has the final authority to determine authenticity, and the role of artists’ estates as legacy guardians.