Civil procedure serves a multitude of goals, from regulating the cost of fact gathering to dictating the rules of advocacy in court to promoting public participation in trials. To what extent can procedural design serve them all, or must rules sacrifice some interests to serve others? In this Article, we are the first to introduce a theory of procedural design that answers this question. We build upon the fundamental insight that the goals of civil procedure, as varied as they are, all occupy a common conceptual space—each addresses an externality, positive or negative, that litigation creates. This insight allows us to tie together distinct strands of scholarship on procedural design, develop a taxonomy of externalities that civil procedure addresses, and propose (sometimes radical) reforms that would allow procedure to serve more of its goals at once.

First, we show that the literature on procedural design has unraveled into three distinct strands. The first strand centers on the interest in reducing cost and delay in litigation. The second strand centers on the interests in limiting gamesmanship between the parties and improving court accuracy in decision-making. The third strand centers on the many related interests in the positive effects of procedure on society, such as developing legal precedent, deterring unwanted (primary) behavior, and so on.

Second, we tie together these strands of the literature by observing that each strand is focused on how procedure can address one type of externality. The first strand of the literature addresses what we call “system externalities”—the effects of actions on other cases in the same court or court system. The second strand addresses what we call “strategic externalities”—the effects of a party’s actions on opposing parties in the same case. The third strand implicates external effects on society as a whole, which we call “public-goods externalities.”

民事诉讼程序服务于多个目标，从规范收集事实的成本到规定法庭辩护规则，再到促进公众参与审判。程序设计可以在多大程度上为他们服务，或者规则必须牺牲一些利益来服务其他人？在本文中，我们是第一个介绍回答这个问题的程序设计理论的人。我们建立在基本洞察力的基础上，即民事诉讼的目标尽管千差万别，但都占据了一个共同的概念空间——每个目标都解决了诉讼产生的积极或消极的外部性。这种洞察力使我们能够将关于程序设计的不同学术领域联系在一起，开发民事程序解决的外部性分类，

首先，我们表明有关程序设计的文献已分解为三个不同的分支。第一条重点关注降低成本和延迟诉讼。第二条重点关注限制当事人之间的博弈和提高法院决策准确性的利益。第三部分集中在程序对社会的积极影响中的许多相关利益，例如制定法律先例、阻止不想要的（主要）行为等。

其次，我们通过观察每一部分都集中在程序如何解决一种外部性上，将这些文献联系在一起。文献的第一部分涉及我们所说的“系统外部性”——同一法院或法院系统中的其他案件的行动的影响。第二部分涉及我们所说的“战略外部性”——同一案件中一方的行为对对方的影响。第三条涉及对整个社会的外部影响，我们称之为“公共物品外部效应”。