Humans and animal populations are increasingly exposed to chemicals in the environment throughout their lifetime, during reproduction and ontogeny. GREEN Tox (Group for Reproductive, Endocrine and Environmental Toxicology) conducts research at two levels: (1) longterm toxicology of environmental chemicals (including cosmetics and flame retardants) with focus on endocrine effects, the developing organism and reproduction, and (2) development of new refined test methods for the characterization of endocrine activity and developmental toxicity of chemicals. Rational actions require reliable information. We are therefore working along two lines: conducting research and providing information to the scientific community and to the public.