The New Orleans disaster in the wake of Hurricane Katrina and Rita points to the need to reconsider the strategies for providing flood risk protection that have been implemented over the years in the flood-prone city. The levee system and other anti-flood equipment deployed during the past decades on sites throughout the city are clearly not efficient, and show the extent to which structures alone are insufficient for protection against flood events. Reducing site vulnerability is possible but difficult, and requires that a coherent political configuration be coupled with a systemic management approach.