No discourse seems more hollow at the present moment than that about tolerance and freedom of expression: in Western culture these concepts are scarcely capable any longer of generating meanings that apply and appeal to all of us. The codes, rules, agreements and symbols that determine our freedoms and rights within the public domain have ceased to function effectively. Leaving cynicism and nihilism behind, the politico-philosophical concept of the public sphere needs to be articulated anew. The desire for this is projected not just onto politics, but also onto art, architecture and the city. Open 10 brings together analyses, stances and proposals of theoreticians and artists.