National regulation is frequently premised on scientific assump- tions; much of regulatory design is based on scientific findings. Con- sumer product, food and drug and workplace safety standards all depend on a scientific assessment of the risks faced by the public and of the efficacy of an adopted measure in addressing these risks. Build- ing codes, waste disposal protocols and mandated immunization of school children all proceed from the technical recommendations of the scientific community. In current Western society, a regulatory measure lacking a scien- tific basis will be subject to criticism and perhaps ridicule; it may be struck down as exceeding the prescriptive powers of the regulator.’ Science identifies areas for regulatory action while limiting the field of possible responses. Not all human needs or desires can be usefully pursued through regulatory means; there is little our public institu- tions can do to address the eventual implosion of the sun. Science cannot at present show us how to harness nuclear fusion, predict earthquakes or prevent hair loss; it cannot cure cancer or AIDS.