In English, the words "agent" and "representative" are in most cases interchangeable, although the latter is term with broader meaning. In the practice of Anglo-American civil procedures, only a lawyer may appear at the court to argue the case on behalf of a party in a lawsuit, and he is simply called "attorney (or counsel) for the plaintiff (or defendant)". The term "agent (or representative) ad litem" is actually unknown in Anglo-American system. But, to translate the Chinese legal term 民事訴訟代理人 into nearly equivalent and understanble English, there seems no better solution than literal translation, because the Chinese term represents a much broader concept than "attorney for plaintiff or defendant." The phrase "in civil action," however, may be omitted unless it is absolutely necessary for clarity.

In Chinese law, the legal relation between 委任人 and 受任人 is based on a contract of mandate (委任合同),also called contract of agency by mandate (委任代理合同), which is a civil law concept. In the civil law system, a mandate is a contract by which one person (the mandator) requests someone (the mandatary) to perform some service. (Black's Law Dictionary) It is similar to a contract of agency in Anglo-American law. In Chinese law, the terms 委任人 (mandator)and 本人 (principal) are used interchangeably. So are the terms 受任人 (mandatary)and 代理人 (agent). It must be pointed out, however, that the Chinese statutory term for 委任 is 委托, although they mean exactly the same thing.