The Comprehensive Environmental, Response, Compensation and Liability Act of 1980, also known as CERCLA or 'Superfund' was enacted by the US Congress in 1980 in response to public concern over the effect of abandoned hazardous waste sites. Perhaps most well known as the US Environmental Protection Agency's primary authority for responding to contaminated properties, CERCLA created one of the broadest liability schemes in the history of US civil law. Following the federal government's lead, most of the 50 US states enacted their own cleanup laws in the 1980's. The states then took the lead in amending those laws in the 1990's in response to the brownfields redevelopment movement. Both CERCLA and the state laws patterned after CERCLA focus on liability for owners, operators and others associated with contaminated sites, the process for investigating and cleaning up those sites, and the contribution or recovery of cleanup costs from liable parties. This article briefly summarizes the basic function of CERCLA and how the 2002 Brownfields Amendments to CERCLA changed federal cleanup law in the US.