"Hacking for the Commons", this 87 minute long documentary takes us to meet with those who, from India to the United States via Europe, are experimenting with the emancipation tools of "free software" in order to bring concrete solutions in a multitude of fields in which collective practices known as "open" - thus "non-proprietary" - are spreading : in agriculture, with "free" seeds, in health, with Open Source medicines, or in education, thanks to a free access to knowledge... Resistants of the "Free" software field see it as a philosophical and political issue, as much as a societal choice, while the contributory and emancipatory practices of "Free" software are beginning to spread far beyond the IT field alone, for the benefice of the Commons...