This paper examines factors related to environmental liability disclosure decisiions for firms in industries with substantial Superfund site involvement. We hypothesize that the extent of disclosure about environmental liabilities is associated with five factors: (1) regulation, including enforcement activity, (2) managements’ information, including site uncertainty and allocation uncertainty, (3) litigation and negotiation concerns, (4) capital market concerns, and environmental liability disclosure, based on disclosures in firms’ annual reports and Forms 10-K, and proxies for the five factors, based on information form other public sources, including the EPA. We find that all of our hypothesized factors except site uncertainty significantly influence firms’ environmental disclosure decisions.