Class action lawsuits—that is, lawsuits by representative parties on behalf of a group of similar plaintiffs that have aggregated their claims in a single action—are frequently in the forefront of debates over the American private law system. According to the Supreme Court, class actions are the "most adventuresome" innovation in American law. To some commentators, the class action device is the tool that "gives American workers and consumers the power and ability to level the playing field, even when facing the most powerful corporations in the world." To others, class actions are typically brought "to essentially shakedown a defendant—hurting businesses and the American economy." Unsurprisingly then, class actions have been a frequent subject of debate in Congress. This report serves as a primer on class action law and analyzes areas that have been the focus of congressional discussions concerning class actions. The report first discusses the broader public policy debate over class actions, including why class actions exist and what risks they pose to the American system of civil justice. The report then details what a plaintiff is required to show under the Federal Rules of Civil Procedure in order to achieve class action "certification"—that is, in order to pursue an action on behalf of an entire class. Throughout, the report addresses the ways in which the Supreme Court and lower federal courts have attempted to balance the benefits of class actions against their potential drawbacks. Lastly, this report discusses key aspects of class action litigation that have been the focus of recent congressional legislative debates. In particular, the report focuses on three areas which have been of particular concern: (1) the cohesiveness (or lack thereof) of the class; (2) ascertainability and administrative feasibility of the class action; and (3) divergent incentives and fees for class counsel compared with the benefits received by class members. The main lens for considering these areas is the Fairness in Class Action Litigation and Furthering Asbestos Claim Transparency Act of 2017 ( H.R. 985 ), which passed the House of Representatives in March 2017. Accordingly, this report considers how H.R. 985 would modify existing law, along with other potential avenues for change. The default rule in American litigation is that a lawsuit is conducted by, or on behalf of, the named parties only. Class actions, however, are an exception to this rule. A class action is a procedure by which a large group of entities—that is, a "class" —may challenge a defendant's allegedly unlawful conduct in a single lawsuit, rather than through numerous, separate suits initiated by individual plaintiffs. Class actions have an ancient pedigree; analogues to class actions "have been recognized in various forms since the earliest days of English law," and class actions have "been a fixture" of federal litigation in the United States "for over seventy-five years." Under the modern version of the class action, a plaintiff (known as the "class representative," the "named representative," or the "named plaintiff") may sue the defendant not only on his own behalf, but also on behalf of other entities (the "class members") who are similarly situated to the class representative in order to resolve legal or factual questions that are common to the entire class. To illustrate, if, for example, a large number of consumers all purchased a product that turned out to be defective, one of those consumers could potentially bring a single class action against the manufacturer on his own behalf as well as on behalf of all others who purchased the product, thereby eliminating the need for other plaintiffs to join that consumer's lawsuit or initiate their own separate lawsuits. Importantly, a class action differs from other forms of litigation involving large numbers of injured persons. In ordinary multiparty litigation, everyone seeking relief from the defendant is a party to the lawsuit and directly participates in the litigation. In a class action, by contrast, the class representative is "the only plaintiff[] actually named in the complaint"; the class members are not formal parties to the lawsuit and typically do not directly guide the litigation. The class representative therefore "acts on behalf of the entire class." The class members, by virtue of not being directly "present before the court," are often referred to as being "absent" from the litigation. The Supreme Court has recognized that the class action device serves several purposes. First, as the Supreme Court has explained, a "principal purpose" of class actions is to advance "the efficiency and economy of litigation." By consolidating what would normally be multiple suits or a multiple-plaintiff litigation into a single suit sharing common questions, the class action is "designed to avoid . . . unnecessary filing of repetitious papers and motions." If every plaintiff had to independently prove and answer the same common questions, it would typically be "grossly inefficient, costly, and time consuming because the parties, witnesses, and courts would be forced to endure unnecessarily duplicative litigation." Class actions thereby potentially economize litigation by consolidating every class member's claim into a single proceeding. A class action also enables large numbers of persons injured by a defendant's unlawful conduct "to obtain relief as a group" when each class member's individual claim is "too small to justify the expense of a separate suit." Oftentimes, when a defendant inflicts comparatively small injuries to a large number of people, no plaintiff standing alone has a sufficient financial "incentive . . . to bring a solo action prosecuting his or her rights." As the Supreme Court has noted, a class action resolves this "problem by aggregating the relatively paltry potential recoveries into something worth someone's (usually an attorney's) labor." To illustrate, suppose a defendant injures a million consumers for $30.00 in damages each. If each plaintiff had to file a stand-alone suit to recover the money he lost, few would take the trouble to do so. As former federal Judge Richard Posner once colorfully noted, "Only a lunatic or a fanatic sues for $30" because the costs of prosecuting the lawsuit would far exceed the maximum award each victim could recover. Thus, some legal observers have argued that absent some other deterrent, like a successful criminal prosecution, the defendant's $30 million wrong would go unpunished, and the victims would remain uncompensated. If, however, an individual plaintiff could bring a single class action lawsuit on behalf of everyone the defendant wronged to resolve the common questions, then the plaintiff could potentially aggregate each class member's $30.00 loss, resulting in a potential $30 million recovery. That $30 million potential award would then make it economically rational for attorneys to expend time and resources to pursue the class's claims. Then, if the plaintiff ultimately prevailed in his class action, the resulting award could be divided among the plaintiff, his counsel, and the other class members. In this way, class actions compensate victims who might otherwise go uncompensated and punish wrongdoers who might otherwise go unpunished. However, as explained in greater detail below, a court's decision to not allow a particular lawsuit to proceed as a class action can effectively "sound the 'death knell' of the litigation on the part of the plaintiffs" because the individual plaintiff's claim will often be "too small to justify the expense of" prosecuting a non-class action lawsuit. Lastly, the Supreme Court has stated that the class action serves to protect defendants from repeated and possibly inconsistent adjudications. By consolidating all potential plaintiffs' claims in a single proceeding, a defendant can obtain finality with respect to all future actions, rather than be subject to an unknown number of repeated suits and possibly inconsistent judgments. Finality benefits defendants by freeing them from "the distraction of litigation" and by allowing them to "proceed with [their] business affairs more clearly." While the Supreme Court has recognized that the class action device serves several useful purposes, the procedural mechanism also poses risks for the U.S. civil justice system. First, because a class action permits thousands or millions of class members to aggregate their claims, a defendant who opts to defend rather than settle a class action may face "potentially ruinous liability." Consequently, "even if a class's claim is weak, the sheer number of class members and the potential payout that could be required if all members prove liability might force a defendant to settle a meritless claim in order to avoid breaking the company." Thus, without effective legal safeguards, class actions could potentially encourage plaintiffs to file lawsuits that have minimal chances of success in order to extract settlements from defendants. While it would of course be inaccurate to conclude that all class actions are meritless or abusive, it is fair to say that plaintiffs have sometimes attempted to bring class action lawsuits that could charitably be described as fanciful or humorous. To name one example, a resident of California sued the manufacturer of Cap'n Crunch cereal for deceptive advertising, contending that the defendant had unlawfully misled consumers to believe that "Crunchberries" were made of fruit. The court presiding over that case, rather than permitting the case to proceed as a class action, dismissed the case in its entirety, opining that "the survival of the [plaintiff's] claim would require th[e] Court to ignore all concepts of personal responsibility and common sense." Additionally, even though class actions may economize litigation in some respects, class action litigation still "place[s] an enormous burden of costs and expense upon parties." As one federal district judge has maintained, almost "all class action law suits involve complex issues, which are costly to resolve and often result in protracted proceedings." Secondly, the fact that a class action permits a named plaintiff to represent absent class members raises the concern that the named plaintiff may not always zealously represent the class's interests. As noted above, class action litigation "is 'an exception to the usual rule that litigation is conducted by and on behalf of the individual named parties only.'"