Legal standing, often called locus standi, is the legal requirement that a person or entity has a sufficient stake or connection to a matter to bring a case or participate in a lawsuit. In other words, it answers whether the party has the right to sue or seek relief in court, and whether the court can legally hear their claims. Key aspects

• Direct harm or injury: The plaintiff must show they have suffered or imminently will suffer a concrete, personal harm that the court can remedy. This is the most common basis for standing in civil cases.

• Nexus to the issue: There must be a meaningful link between the plaintiff’s stake and the legal question or statute at issue. The connection helps ensure the court’s decision will matter to the party.

• Legal interest or role: Standing can arise from direct involvement, statutory rights, or a recognized legal interest (such as a representative or organizational standing in some contexts). Some legal frameworks allow organizations or public-interest groups to sue on behalf of others or the public interest.

• Different standards by forum: Standing rules vary by jurisdiction and by type of action (constitutional, civil, administrative, or class actions). Some systems also recognize automatic or statutory standing in specific contexts (e.g., certain environmental or corruption-related cases).

• Not just about merits: Courts typically first assess standing before addressing the substantive merits of the case. A lack of standing means the case will be dismissed without consideration of the claims.

Practical examples

• A person who alleges direct personal injury from a defective product generally has standing to sue manufacturers or retailers for damages.

• A taxpayer challenging a law’s constitutionality on the basis of “chilling effects” might rely on standing principles to show that enforcement would affect others’ rights, even if the taxpayer is not personally harmed. The precise reach depends on jurisdiction.

• In some contexts, statutes or rules grant automatic standing to certain parties (for example, public-interest groups or environmental agencies), permitting suits even without direct personal harm.

If you want, I can tailor this to a specific jurisdiction (for example, the United States, the European Union, or a particular country) and to a particular type of case (constitutional challenges, civil actions, environmental cases, or class actions).