Tort reform refers to changes in the civil justice system in common law countries that aim to reduce the ability of plaintiffs to bring tort litigation (particularly actions for negligence) or to reduce damages they can receive. Such changes are generally justified under the grounds that litigation is an inefficient means to compensate plaintiffs; that tort law permits frivolous or otherwise undesirable litigation to crowd the court system; or that the fear of litigation can serve to curtail innovation, raise the cost of consumer goods or insurance premiums for suppliers of services (for example medical malpractice insurance), and increase legal costs for businesses. Tort reform has primarily been prominent in common law jurisdictions, where criticism of judge-made rules regarding tort actions manifests in calls for statutory reform by the legislature.

United States.

Tort reform advocates frequently contend that too many of the lawsuits filed in the United States each year are "frivolous" lawsuits. The term "frivolous lawsuit" has acquired a broader rhetorical definition in political debates about tort reform, where it is sometimes used by reform advocates to describe legally non-frivolous tort lawsuits that critics believe are without merit, or award high damage awards relative to actual damages. In the United States, tort reform is a contentious political issue. US tort reform advocates propose, among other things, procedural limits on the ability to file claims, and capping the awards of damages. Opponents of tort reform argue that reformers have misstated the existence of any real factual issue and criticize tort reform as disguised corporate welfare.

Tort reform advocates argue that the present tort system is too expensive, that meritless lawsuits clog up the courts, that per capita tort costs vary significantly from state to state, and that trial attorneys too often receive an overly large percentage of the punitive damages awarded to plaintiffs in tort cases. (The typical contingent fee arrangement provides for the lawyer to retain one-third of any recovery.) A Towers Perrin report indicates that U. S. tort costs were up slightly in 2007, are expected to significantly increase in 2008, and shows trends dating back as far as 1950. More recent research from the same source has found that tort costs as a percentage of GDP dropped between 2001 and 2009, and are now at their lowest level since 1984. High-profile tort cases are often portrayed by the media as the legal system's version of a lottery, where trial lawyers actively seek the magic combination of plaintiff, defendant, judge, and jury. Advocates of tort reform complain of unconstitutional regulation caused by litigation, and that litigation is used to circumvent the legislative process by achieving regulation that Congress is unwilling or unable to pass.