This project aims to understand the cognitive models, assumptions, and inference methods the comprise the layperson's system of "intuitive toxicology" and to compare this system with the cognitive models, assumptions, and inference methods of toxicologists and risk assessors. Such comparisons would expose the similarities and differences within the expert and lay communities as well as the differences between lay perceptions and expert views. Several empirical studies will be designed, conducted, and reported during the course of this project. These studies should produce clearer, better articulated representation of the conceptual frameworks that exist for experts and laypeople with regard to chemical hazards and the scientific methods used to assess chemical risks. Such representations are crucial for improved methods of risk assessment and for the development of a risk-management process that replaces polarized social conflict with effective multi-way communication about chemical risks and benefits.