Editors' Summary: Congress, through the 1986 Superfund Amendments and Reauthorization Act (SARA), has succeeded in promoting CERCLA settlements between potentially responsible parties (PRPs) and the government. But the growing number of settlements have resulted in increased litigation between settling and nonsettling PRPs, in part due to uncertainties about SARA's contribution provisions. SARA clarified that settling PRPs may seek contribution from other liable parties, and obtain protection from contribution actions related to matters addressed in their settlements. Unfortunately, Congress left unclear the extent to which settlements limit nonsettlors' liability, which settlement "matters" are accorded contribution protection, and how contribution protection applies to PRPs who settle at different times and over different issues. The author analyzes CERCLA's contribution provisions, their legislative history, and the apparent inconsistencies in key court decisions shaping their application. He explores the effect of contribution protection on nonsettling parties and private cost recovery actions, and the impact of PRP settlement timing on contribution claims and protection. The author concludes that Congress intended to punish nonsettling parties by saddling them with disproportionate liability. His analysis of cases interpreting CERCLA's contribution provisions supports recovery of private response costs voluntarily incurred, even against those parties with contribution protection. The author also concludes that the scope of contribution protection in de minimis settlements should generally be broad to provide final resolution of claims against de minimis parties.