The manifesto of the Groupe d’information sur les prisons, authored by Foucault, Pierre Vidal-Nanuet and Jean-Marie Domenich, which I translated for this site a couple of years ago, has been reprinted in Viewpoint magazine. The prison group, along with Foucault’s involvement in the parallel health group and other activist work are discussed in detail in Foucault: The Birth of Power.
Foucault News 