studied cultural anthropology and history of art in Hamburg and Munich. He was head of Kunsthalle Düsseldorf from 1972 to 1996, after which he worked as founding director of the Museum Kunstpalast. He has lived in Berlin since 2003. He has curated pioneering exhibitions such as those on Marcel Broodthaers (1972), Gerhard Richter (1986), Anselm Kiefer (1984), Pollock/Siqueiros (1995), Michail Wrubel (1997) and Caravaggio (2006). He was appointed main German curator of »Berlin-Moscow/Moscow-Berlin 1950–2000« (2003–04) by the Berliner Festspiele, which included comprehensive exhibitions in the Martin-Gropius-Bau in Berlin and the State Historical Museum in Moscow.