How are we to understand works of art that are realized with the physical involvement of the viewer? A relationship between a work of art and its audience that is rooted in an experience that is both aesthetic and physical? Today, these works often use digital technologies, but artists have created participatory works since the 1950s. In this book, critics, writers, and artists offer diverse perspectives on this kind of "practicableż art that bridges contemplation and use, discussing and documenting a wide variety of works from the last several decades. The contributors consider both works that are technologically mediated and those that are not, as long as they are characterized aby a process of reciprocal exchange.