This document discusses the key concepts of agency law, including: - The definition of a principal and agent in a contract of agency - The power of attorney and how it allows an agent to act on behalf of a principal - The general rules that whatever a person can do, they can do through an agent, and that the acts of an agent are considered the acts of the principal - The differences between agents, servants, and contractors - The duties and rights of both principals and agents in a contract of agency - When an agent can delegate their authority to a sub-agent, and the differences between a sub-agent and substitute agent.