Dennis Oppenheim was an American conceptual artist, performance artist, earth artist, sculptor and photographer. Dennis Oppenheim's early artistic practice is an epistemological questioning about the nature of art, the making of art and the definition of art: a meta-art that arose when strategies of the Minimalists were expanded to focus on site and context. As well as an aesthetic agenda, the work progressed from perceptions of the physical properties of the gallery to the social and political context, largely taking the form of permanent public sculpture in the last two decades of a highly prolific career, whose diversity could exasperate his critics.