Those, who were able and willing to offer resistance, looked for company because one single person had almost no chance. Resistance groups were formed in the camp from people of same political opinions or nationalities. Two necessary preconditions for resistance were to put people of confidence to all important functions and a working prisoner's intelligence service. Main issues of the illegal work were preparing escapes and planning armed uprisings.

An important role within the Austrian resistance group was played by Ernst Burger.

One of the largest, if not the largest act of resistance took place on October 7, 1944 in Auschwitz-Birkenau. Prisoners who worked in the "Sonderkommando", more than 400 mostly Hungarian and Greek Jews, blew up crematorium IV, attacked SS-guards with self-constructed hand-grenades and tried to flee.

The uprising was put down by the SS; all persons involved were shot, the SS lost three men, but the crematorium remained out of order.

A group of Jewish women who worked in the munition factory "Union" in Auschwitz, delivered gunpowder which they had smuggled out of their factory under difficult conditions. The powder was handed out to a member of the resistance group who worked in the clothing storehouse and then to the "Sonderkommando". The gunpowder made it possible to carry out the uprising.

The Political Department of Auschwitz concentration camp needed extensive investigations to find out that the gunpowder came from the Union-factory. The women involved were tortured for a couple of days, but didn't tell the names of the other secret organisation's members. The four Jewish women were hung on January 6, 1945, three weeks before the liberation of Auschwitz. The execution was the last one of this manner before soldiers of the Red Army liberated the camp.