Uncertainty, complexity and post-normal science

Abstract The quality of the scientific inputs to the policy process is known to be problematic. No one can claim “truth” for his results. Nor can uncertainty be banished, but good quality can be achieved by its proper management. The interaction of systems uncertainties and decision stakes can be used to provide guidance for the choice of appropriate problem-solving strategies. When either or both of these are high, then mission-oriented applied science and client-serving professional consultancy are not adequate in themselves, and an issue-driven post-normal science is necessary. Just as in cases with ethical complexities (as in biomedical science) there must be an “extended peer community,” including all stakeholders in the dialogue, for evaluating quality of scientific information for the policy process.