Art forgery is the creation and sale of works of art which are falsely credited to other, usually more famous artists. Art forgery can be extremely lucrative, but modern dating and analysis techniques have made the identification of forged artwork much simpler.

Authenticity in art is manifest in the different ways that a work of art, or an artistic performance, can be considered authentic. The initial distinction is between nominal authenticity and expressive authenticity. In the first sense, nominal authenticity is the correct identification of the author of a work of art; of how closely an actor or an actress interprets a role in a stageplay as written by the playwright; of how well a musician's performance of an artistic composition corresponds to the composer's intention; and how closely an objet d’art conforms to the artistic traditions of its genre. In the second sense, expressive authenticity is how much the work of art possesses inherent authority of and about its subject, and how much of the artist's intent is in the work of art.