The London Guardian is probably right when, in an article at the beginning of last year, it speaks of the shocking nature of Santiago Sierra's work being probably less to do with the fact that he tattooed some junkies in exchange for a hit, but rather with those small shifts in perception which brutally remind us that ultimately the horror of the daily human rights violations leave us quite cold. Since Santiago Sierra studied in the late 1980s in Hamburg, he has the reputation of seing candalous. Santiago Sierra doesn't simply depict these realities, he also allows us to experience them first-hand - how else can one understand his erecting a wall in the Spanish Pavilion at the 50th Venice Biennale in 2003 and commissioning a security firm to police the back door and only admitted those visitors who were able to provide Spanish or Mexican identity documents? This comprehensive book on the retrospective exhibition has been compiled by the artist himself, and offers an overview of the work.