A class action is a type of lawsuit in which one or a few plaintiffs seek to represent hundreds or thousands of plaintiffs with the same or similar claims against the same defendants. Rules of procedure in state and federal courts permit class actions in limited circumstances for the purpose of resolving similar disputes more efficiently than if each plaintiff filed a separate lawsuit.

In Kansas, class action lawsuits are governed by Chapter 60 of the Kansas Statutes Annotated, specifically K.S.A. 60-223, which is similar to Rule 23 of the Federal Rules of Civil Procedure. This statute allows one or more plaintiffs to represent a larger group, or 'class', in a lawsuit if the class is so numerous that individual lawsuits would be impractical, there are questions of law or fact common to the class, the claims or defenses of the representative parties are typical of the claims or defenses of the class, and the representative parties will fairly and adequately protect the interests of the class. Class actions in Kansas are used to increase the efficiency of the legal process by resolving widespread issues in a single case rather than through multiple lawsuits. They are commonly employed in cases involving consumer fraud, corporate misconduct, securities fraud, and employment practices. Before a class action can proceed, the court must certify the class, ensuring that the aforementioned requirements are met. Additionally, federal law under the Class Action Fairness Act (CAFA) may allow certain class actions to be heard in federal court if they meet specific criteria, such as having a monetary claim exceeding $5 million or involving plaintiffs and defendants from different states.