Forthcoming in the Journal of Law and Economics. "This paper examines the sizes of the fines, damage awards, remediation costs, and market value losses imposed on companies that violate environmental regulations. Firms violating environmental laws suffer statistically significant losses in the market value of firm equity. The losses, however, are of similar magnitudes to the legal penalties imposed; and in the cross section the market value loss is related to the size of the legal penalty. Thus, environmental violations are disciplined largely through legal and regulatory penalties, not through reputational penalties."--Abstract.