Taking place in the skies over London, the plazas of Rotterdam, and the hallways of museums worldwide, a new kind of art has emerged since the 1990s. Known as Relational Art, this controversial practice features audience participation in ways never before realised, often using new media and social networking. In this book, academic and artist Craig Smith outlines a rigorous theory of Relational Art, explaining why audience interaction and collective art production has become so relevant. Tracing the development of the movement, from its beginnings with the 1996 Traffic exhibition in Bordeaux and Nicolas Bourriaud's treatise Relational Aesthetics, to the diverse and international scope of Relational Art today, this provocative book explores the foundational impact this movement has had on contemporary art and exhibition making. Taking the reader through a range of case studies, such as Olafur Eliasson's iconic Weather Project at Tate Modern, and uniting ideas from artists, art critics, curators, philosophers and audience members, it reveals the practices integral to the movement and how these have affected aesthetic, theoretical and economic forces in the art world. Through a guided tour of thought-provoking and influential works, he demonstrates that Relational Art has permanently altered the nature of art and its global audiences.