The Prinicipal-Agent Relationship dictates that if the person who is at-fault for an accident was acting to further a business or other relationship, the party receiving the benefit of that relationship (called the principal) may also be liable for the wrongful conduct.
The relationship between the ‘Principal-Agent’ is similar to the ‘Employer-Employee’ relationship in the respect than an agent is performing some sort of conduct on behalf of its principal.
However, the ‘Principal-Agent’ relationship can extend further than the ‘Employer-Employee’ relationship. If the at-fault agent was acting to further a business or other relationship for the principal, the principal may also be liable for the wrongful conduct.
For example, if person A hires person B to clean their home and person B injures someone else in the process, person A may also be held liable to the injured party. Because person B is acting as an agent for person B, the ‘Principal-Agent’ relationship exists.