After the sanitary disaster caused by the first months of the conflict, the Health service of the French armies undertook a true revolution. By 1918, it had become the most efficient of all the opposing armies. At the end of 1914, through the spacing out of the evacuating hospitals within the zone of the armies, the most efficient teams were placed as close as possible to the front. Injured soldiers were categorized at every step of the chain. Technical progress, especially in war surgery, pushed medicine into the moderne era.