Agency law is concerned with any "principal"-"agent" relationship; a
relationship in which one person has legal authority to act for another.
Such relationships arise from explicit appointment, or by implication.
The relationships generally associated with agency law include
guardian-ward, executor or administrator-decedent, and
employer-employee.
Standing, or locus standi, is capacity of a party to bring suit in
court. State laws define standing. At the heart of these statutes is the
requirement that plaintiffs have sustained or will sustain direct
injury or harm and that this harm is redressable.
At the Federal
level, legal actions cannot be brought simply on the ground that an
individual or group is displeased with a government action or law.
Federal courts only have constitutional authority to resolve actual
disputes. Only those with enough direct stake in an action or law have "standing" to challenge it.
In contract
law, a person's ability to satisfy the elements required for someone to
enter binding contracts. For example, capacity rules often require a
person to have reached a minimum age and to have soundness of mind.