This article addresses the role of public contracts and of public-private networks in relation to the new cognitive infrastructure of postmodern societies and the rise of an experimental rationality. The use of contracts in public law has evolved: it is no longer just a new version of the administrative decision; it is now used as a means in a broad process of breaking up the permeability of public administration. New modes of contracting are a response to increasing fragmentation of interests in industry and in society as a whole. This evolution has also given rise to the concept of the network society. Certain normative challenges have to be met in postmodern administration. The administrative act is always limited by the effect of the ...