U.S. society has adopted and adapted scientific techniques for purposes of social control of risk. These techniques incorporate numerous, and potentially large, uncertainties. They also serve numerous, different social goals--scientific accuracy, social acceptability, the need for timely decisions, consistency over time, fairness to the parties concerned, protection of public health and environments, etc.--although most commentators have emphasized only the aim of scientific accuracy. The law has developed a number of evidentiary procedures to guide decision making under uncertainty and to serve the many social goals a legal system has. Using aspects of the law as a model, this interdisciplinary team aims to design evidentiary rules for carcinogen risk assessment that can help to reduce some of the uncertainties and serve better some of the social goals of risk assessment. The research involves determining which evidentiary rules used in legal proceedings might be adapted for use in carcinogen risk assessments and examining the impact their adoption might have on the social goals of these assessments. During this phase, research will focus on serving the goals of scientific accuracy and expeditiousness, which may conflict, and on developing procedures that can serve other goals of risk assessment and adjudicate conflicting goals and evidentiary procedures. Results will be disseminated in presentations and via appropriate scholarly and public policy journals. This approach offers a broader perspective on risk assessment. It recognizes the substantial uncertainties inherent in it, provides a comprehensive way of coping with them and offers some wider alternatives for thinking about the process. This project involves a collaboration between a biochemist/pharmacologist, statistician, environmental engineer, resource economist and legal philosopher. The topic is very important; the research team, well qualified; institutional support is good. Results are likely to be of high quality and broadly disseminated. Support is therefore recommended.