A broker-dealer is a financial firm that acts as both a broker and a dealer. As a broker, the firm facilitates transactions between buyers and sellers of securities. As a dealer, the firm buys and sells securities for its own account. Broker-dealers play a crucial role in the securities markets by connecting buyers and sellers and providing liquidity to the market. They also offer services such as underwriting new securities, providing market research and analysis, and offering investment advice to their clients. Some broker-dealers are large, full-service firms that offer a wide range of products and services, while others specialize in specific areas of the market. The activities of broker-dealers are regulated by the Securities and Exchange Commission (SEC) and the Financial Industry Regulatory Authority (FINRA).