Since 1977, he has been a contributing editor to Artforum, in New York; in 1987, he received The Frank Jewett Mather Award from CAA, The College Art Association of America; since 1989
until 2008, he has been the Senior Curator of Contemporary Art at the Solomon R. Guggenheim Museum, in New York; since 1991 he has been contributing editor to Interview, in New York; from 1995 to 2014, he was the director of Fondazione Prada, Milan; in 1996 he was artistic
codirector of the first Biennale di Arte & Moda, Firenze; in 1997, he was appointed Curator of the 47th Esposizione Internazionale d'Arte.