| Term | Definition |
| Express Authority | embodied in which the principal has engaged the agent to do. (orally or in writing). |
| Equal Dignity Rule | If contract is or must be in writing, agents authority must also be in writing. Failure to do so makes contract voidable at the option of the principal. |
| Power of Attorney | Confers express authority upon the agent. Written document, that is notarized. Special or General. Terminates on incapacity/death. |
| Implied Authority | Conferred by custom, inferred, or implied as reasonably necessary to carry out express authority. |
| Apparent Authority | Principal, by word or deed, causes a third party reasonably to believe that the agent has authority to act, without express or implied authority. |
| AA through Pattern of Conduct | Principal's actions over time lead third party to believe that an agency relationship exists, agency by estoppel (principal estopped from denying the agent had authority). |
| AA through Possession of Property | Apparent authority based on possession/ownership of property. Principal cannot cancel sale or agreement. Principal has 'clothed the agent' with possession and ownership. |
| Emergency Powers | Unforeseen emergency demands action by the agent to protect or preserve the property and rights of the principal, agent is unable to communicate with the principle, agent has emergency power. |
| Ratification | Occurs when the principal affirms an unauthorized act by agent. Express or Implied. If not ratified than unaccepted offer. |
| Express Authority | Occurs when the principal affirms an unauthorized act by agent. Express or Implied. If not ratified than unaccepted offer. |
| Requirements for Ratification | Identified principal who ratifies. Act affirmed in its entirety. Affirmance before withdrawal. Principal has capacity at time of K formation and affirmance. Principal knows all material facts. |