To resolve the theoretical ambiguity in the effect of age on the value of statistical life (VSL), this article uses a novel, age-dependent fatal risk measure to estimate age-specific hedonic wage regressions. VSL exhibits an inverted-U-shaped relationship with age. In the year 2000 cross section, workers' VSL rises from $3.7 million (ages 18–24) to $9.7 million (35–44), and declines to $3.4 million (55–62). Controlling for birth-year cohort effects in a minimum distance estimator yields a peak VSL of $7.8 million at age 46, and flattens the age-VSL relationship. The value of statistical life-year also follows an inverted-U shape with age.

We synthesize and review retrospective analyses of federal air quality regulations to examine the contributions of the Clean Air Act (CAA) to the vast air quality improvements seen since 1970. Geographic heterogeneity in stringency affects emissions, public health, compliance costs, and employment. Cap-and-trade has delivered greater emission reductions at lower cost than conventional mandates, yet has fallen short of textbook ideals. Market power also influenced the CAA’s benefits and costs. New benefit categories have been identified ex post, but specific technology requirements have not yet been rigorously evaluated. Comparisons of aggregate benefits and costs of the CAA are beyond present capabilities. (JEL D61, K32, Q51, Q53, Q58)

This paper provides (for the nonspecialist) a highly streamlined discussion of the main issues, and controversies, in the design of climate mitigation policy. The first part of the paper discusses how much action to reduce greenhouse gas emissions at the global level is efficient under both the cost-effectiveness and welfare-maximizing paradigms. We then discuss various issues in the implementation of domestic emissions control policy, instrument choice, and incentives for technological innovation. Finally, we discuss alternative policy architectures at the international level. (JEL Q54, Q58)