In the past thirty years, Dan Graham has proved himself to be a wide-ranging artist. His work consists of performance art, installations, video, sculpture, and photography. Few of Graham's works have been commissioned or exhibited in the United States. In fact, the only major work commissioned in the U.S. in the last decade was the Rooftop Urban Park Project, in which he designed the piece "Two-Way Mirror Cylinder Inside Cube and Video Salon" (1981–1991). Some other commissions in the U.S. are "Yin/Yang" at MIT, the labyrinth at the Minneapolis Sculpture Garden, and at Middlebury College, and in Madison Square Park.