A member of a stock exchange who is assigned to a particular security or securities for which he has to maintain order and stability in their trading. He does this by standing ready to buy and sell the securities for his account when there is a temporary imbalance in demand and supply. The activities of the specialist prevent wide movements in prices which could destabilize a stock market. The specialist, unlike the floor broker, has no direct dealings with investors (the public), but in addition to buying for his own account, he assists floor brokers execute limit orders.