According to mainstream policy wisdom, knowledge utilization is a function of both political and scientific consensus. The substantial technical core in environmental policy, and its wide-ranging impacts on decisions and behaviors of firms, households, and consumers, only underscores this double requirement. This chapter argues that the problematic relationship between knowledge use and political choice can be understood as a particular instance of boundary work at the politics-science nexus, that is, the dialectics between the scientization of politics and the politicization of science. Problem structuring, like the idea of quality control through extended peer review, aims at an escape from the potential dilemma between democratic political choice and technocratic use of scientific knowledge. The problem thus appears to be moderately structured. However, there is evidence that the theory fails to grasp the real life situation with respect to Dutch fisheries.