An Attorney-in-Fact, or an agent as referred to in some states is someone specifically named by another through a written “power of attorney” to act for that person in the conduct of the appointers business. In general, the attorney-in-fact is authorized to conduct any business or sign any document on behalf of the individual, but not necessarily authorized to practice law.

As an example:
Where real estate matters are concerned, the power of attorney must be formally acknowledged before a notary public so that it can be recorded along with the real estate deed, deed of trust, mortgage or other document.