Explosive growth in credit, debit, and other card payment systems in recent years has produced a parallel growth in private dispute resolution systems based on the web of contracts entered into by merchants, merchant acquirers, consumers, card issuers, card associations, and transaction processors. These contracts have produced legal systems based on contract and the enforcement of which rests primarily on reputational constraints. To cost-effectively resolve disputes, these private legal systems have evolved innovative procedures using resources at the lowest-possible level, including incentive-payments for producing information and rigid deadlines for parties' actions. This paper describes and analyzes these legal systems and their procedures as a potential model for resolving other categories of disputes.