This baseline assessment provides a summarized description of the Superfund Alternative Approach (SAA), including a brief history of its evolution, its current use, recent SAA evaluation findings, the current practice on seeking state concurrence on National Priorities List (NPL) listings, NPL-listing factors, and recommendations for the future use of SAA. The polluter pays principle is a fundamental tenet of the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA, commonly known as Superfund). Starting in 1989, EPA initiated its Enforcement First policy and began to first look to potentially responsible parties (PRPs) to investigate and clean up Superfund sites before using Fund money. Under this policy, PRPs conduct the majority of remedial actions.