Precaution, environmental science, and preventive public policy.

The Lowell Center for Sustainable Production has sought to engage scientists, policy-makers, advocates, and students in a broad public discussion about whether the tools and methods of environmental science and its integration in policy are adequate to address complex, highly uncertain environmental and health risks. It did so in an International Summit on Science and the Precautionary Principle and a recent collection of analyses stemming from the summit. Here, the author summarizes some summit recommendations to overcome barriers and build momentum for a vision for science and policy that better reflects uncertainty and complexity in natural systems. Appended is a summit statement on the subject.