Different theories on public sphere(s) complete each other or collide in examining the intersubjective relationships involved in organizing and administering the responses of society to the political and economical power repertory. Habermas’s default theory, who invokes the critical participation of every citizen in the public communication, is rather extended in the countertheories represented by Fraser’s “subaltern counterpublics”, Mouffe’s “agonistic politics” or Hardt and Negri’s “shared commons”. These observations are undertaken by artists in their public art practices and inform the contemporary art theories on audience participation.