In his Condensation Cube displayed in Room 1, German artist Hans Haacke had explored biological systems. In this controversial documentary installation he turns to social systems. Shapolsky et al., Manhattan Real Estate Holdings, a Real Time Social System, as of May 1, 1971, is the product of Haacke’s research into the real estate holdings of the Shapolsky family in Manhattan. Harry Shapolsky had attracted Haacke’s attention because he was the landlord who owned more slum properties than any other landowner in New York. Haacke’s research – all culled from public records – reveals how Shapolsky’s business worked, different properties being held under different company names. The series of 142 photographs of the facades of tenement buildings, accompanied by typewritten data sheets, added up to a biting indictment of the monopoly of one family of wealthy proprietors over the slums of a particular area. Due to be displayed in an exhibition at the Guggenheim Museum in New York entitled Hans Haacke: Systems, the work was deemed ‘inappropriate’ by the museum’s management, and the Guggenheim decided to close down the exhibition. The curator, who defended the work, was fired. As a result of the ensuing furore, Shapolsky et al. became one of the most talked about works of the early 1970s.