This document summarizes the empirical estimates of the values associated with changes in health risks. Previous reviews have not included both the range of estimates found by each study and the rationale for selecting one estimate as better than another for policy questions. The qualifications presented by the study authors, along with their estimates and the context in which they are estimated, are important for interpreting the policy usefulness of these numbers. Prior reviews give these considerations a cursory treatment and when the estimates actually appear in policy assessments, the qualifications tend to disappear entirely. The result often has been inappropriate application of the estimates and, even where applied properly, the level of confidence policy makers should have in the numbers generally has been left unstated. The main report compiles the available empirical estimates and documentation in one reference source, presents a critical discussion of the estimates, and evaluates their usefulness in environmental policy assessment. The primary difference between the two versions is that this summary does not contain a detailed technical discussion.