The COVID crisis triggered a real war against the virus. Civilian or military, medical, paramedical or logistical personnel all joined forces to try to deal with it. At the Hôpital d'Instructions des Armées in Percy, in the south of Paris, this real tour de force is both human and technical. On every floor, the staff was confronted with this crisis situation requiring cohesion, adaptation, commitment, immediate decisions, unprecedented actions... with a common objective: to unite to save lives. What has this crisis changed in their profession?