Viewers of contemporary art are often invited to involve themselves actively in artworks, by entering installations, touching objects, performing instructions or clicking on interactive websites. Why have artists sought to engage spectators in these new forms of participation? In what ways does active participation affect the viewer's experience and the status of the artwork? Spanning a range of practices including kinetic art, happenings, environments, performance, installations, relational and new media art from the 1950s to the present, this critical anthology sheds light on the history and specificity of artworks that only come to life when you - the viewer - are invited to 'do it yourself.' The volume consists of fifteen essays by art historians, critics and curators, which are divided into three sections. Part I addresses the emergence of spectator participation in the 1960s, while Part II brings together in-depth case studies of specific participatory practices in the 1960s, 1970s and 1990s, analysing the issues that they raise in their very modes of operation. The more general critical essays in Part III map out a range of theoretical approaches to the 'do-it-yourself' artwork. Together, the three sections provide invaluable historical perspectives and theoretical tools for scholars, students, artists and readers interested in contemporary art. Rather than a specialist topic in the history of twentieth- and twenty-first century art, the 'do-it-yourself' artwork raises broader issues concerning the role of the viewer in art, the status of the artwork and the socio-political relations between art and its contexts.