Art by long distance: Joseph Kosuth -- Conceptual bureaucracy: Ian Burn, Mel Ramsden, and art and language -- Memory, ruins, and archives: Boyle family -- Memory storage: Anne and Patrick Poirier -- Memory and ethics: Helen Mayer Harrison and Newton Harrison -- Negotiated identity: Christo and Jeanne-Claude -- Eliminating personality: Gilbert and George -- Missing in action: Marina Abramović and Ullay -- Doubles, Doppelgängers, and the third hand.