A real estate broker or real estate agent is a person who acts as an intermediary between sellers and buyers of real estate/real property and attempts to find sellers who wish to sell and buyers who wish to buy. In the United States, the relationship was originally established by reference to the English common law of agency, with the broker having a fiduciary relationship with his clients.

An estate agent being used as a term in the United Kingdom means a person or organization whose business is to market real estate on behalf of clients, but there are significant differences between the actions and liabilities of brokers and estate agents in each country. Beyond the United States, other countries take markedly different approaches to the marketing and selling of real property.

In the United States, however, real estate brokers and their salespersons (commonly called "real estate agents" or, in some states, "brokers")[1] assist sellers in marketing their property and selling it for the highest possible price under the best terms.