A brokerage firm, also called a broker-dealer, is in the business of buying and selling securities – stocks, bonds, mutual funds, and certain other investment products – on behalf of its customer (as broker), for its own bank (dealer), or both. Individuals who work for broker-dealers - the sales personnel are commonly referred to as brokers.

An investment adviser is paid for providing advice about securities to clients. In addition, some investment advisers manage investment portfolios and offer financial planning services.