Causes of action in civil litigation are specific claims provided by law that serve as the basis for parties to a lawsuit to recover money or property from each other—or to provide other legal or equitable relief, such as a court order requiring or prohibiting some act (injunctive relief). Examples of causes of action include breach of contract, fraud, breach of fiduciary duty, and negligence. Causes of action (also called claims) are usually located in a state or federal statute, or in court opinions (common law).

In California, causes of action in civil litigation are the legal grounds on which a plaintiff bases their lawsuit to seek remedies such as monetary compensation, restitution, or injunctive relief. These causes of action can arise from violations of state statutes, such as the California Civil Code or the California Business and Professions Code, or from principles established in case law, also known as common law. For instance, a breach of contract claim would be based on the failure to fulfill the terms of a contract, while a negligence claim would arise from a party's failure to exercise reasonable care, resulting in harm to another. Fraud involves intentional misrepresentation, and breach of fiduciary duty occurs when a party with a duty to act in another's best interest fails to do so. Each cause of action has specific elements that the plaintiff must prove to prevail in court. It's important for parties involved in civil litigation to consult with an attorney to understand the specific requirements and defenses associated with their particular cause of action.