He participated in establishing a section of the "maquis" where he officially became one of the local leaders in the Vercors Plateau and in the Chartreuse Mountains. He helped people to avoid being taken into the "Service du travail obligatoire" (STO), the Nazi forced-labour program agreed upon with Pierre Laval, by creating in Grenoble the first refugee for resistants to the STO; he founded the clandestine newspaper "L'Union patriotique indépendante". For a time, in 1943, he was given shelter by Lucie Coutaz, a Resistance member who later became his secretary and was his assistant in his charity work until her death in 1982.