This article draws upon the law-in-action, repeat players, and motive to understand how legal actors construct the “good case” in dispute settlement systems. The construction of “good cases” is examined at the World Trade Organization (WTO), a relatively new and unexplored site for the study of dispute settlement. Findings show that the good case encompasses flexible sets of motives including economic, political, and symbolic characteristics of trade grievances to mobilize WTO law. The flexibility is due to uncertainties associated with litigation, which are manifestations of four features of the WTO: the newness of the system, the organizational and legal structure of the dispute system, the context of the WTO as an intergovernmental agreement, and the persistence of inequality between states. Six variations of the good case are identified.