Interview: RoseLee Goldberg is an art historian, critic and curator who pioneered the study of performance art. Author of several seminal books, including Performance Art: From Futurism to the Present (1979) and Performance: Live Art from the 1960s (1998), she is the Founding Director of 'Performa', a non-profit organization for the development, commission and presentation of performance art.

Survey: Yilmaz Dziewior is a critic and curator based in Hamburg, where he is professor in art theory at the Hochschule für bildende Künste. Formerly Curator at the Ludwig Museum in Cologne and Director of the Kunstverein in Hamburg, where he organized an exhibition of Zhang Huan's work in 2002, he is currently Co-Curator of the 7th Biennial Exhibition of Visual Arts in Limerick (2009). His writing has been published in Artforum, Camera Austria and Texte zur Kunst, as well as in numerous exhibition catalogues.

Focus: Robert Storr is Dean of the School of Art at Yale University. Formerly Senior Curator at the Museum of Modern Art in New York, he directed the SITE Santa Fe Biennial in 2004 and the Venice Biennale in 2007. He was a contributing author to Phaidon's Alex Katz (2005), Louise Bourgeois (2003) and Raymond Pettibon (2001), and writes regularly for numerous journals and magazines, including Art in America, Frieze and Parkett.