In theory, market-based regulatory instruments correct market failures at least cost. However, evidence on their efficacy remains scarce. Using administrative data, we estimate that, on average, the European Union Emissions Trading System (EU ETS)—the world’s first and largest market-based climate policy—induced regulated manufacturing firms to reduce carbon dioxide emissions by 14–16% with no detectable contractions in economic activity. We find no evidence of outsourcing to unregulated firms or markets; instead, firms made targeted investments, reducing the emissions intensity of production. These results indicate that the EU ETS induced global emissions reductions, a necessary and sufficient condition for mitigating climate change. We show that the absence of any negative economic effects can be rationalized in a model where pricing the externality induces firms to make fixed-cost investments in energy-saving capital that reduce marginal variable costs.

When regulated firms are offered compensation to prevent them from relocating, efficiency requires that payments be distributed across firms so as to equalize marginal relocation probabilities, weighted by the damage caused by relocation. We formalize this fundamental economic logic and apply it to analyzing compensation rules proposed under the EU Emissions Trading Scheme, where emission permits are allocated free of charge to carbon-intensive and trade-exposed industries. We show that this practice results in substantial overcompensation for given carbon leakage risk. Efficient permit allocation reduces the aggregate risk of job loss by more than half without increasing aggregate compensation.