Dealers are people or firms who buy and sell securities for their own account, whether through a broker or otherwise. They act as a principal in trading for their own account, as opposed to a broker who acts as an agent who executes orders on behalf of its clients. They are composed mostly of large banks engaging in money dealing activities—engaging as a counterparty in repo markets. They are important figures in the market. They also help create liquidity in the markets and boost long-term growth.