Account Executive

one who is authorized to manage a client's accounts (for a commission fee)

An account executive is a sales representative. The title is given to higher level members of the sales staff. If the organization also has account managers, the account executive out-ranks them. Smaller organizations may call all of their sales people account executives to give the customers a feeling that their business is important to the organization.In larger organizations, account executives are given direct responsibility for the dealings with one or more high volume customers or clients. These customers or clients, referred to as s, are important to the organization's success, and so an account executive is necessary to manage one or more persons dedicated to serving the needs of the transactions and relationships with the customer.
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Noun
1. someone in charge of a client's account for an advertising agency or brokerage or other service business
(synonym) account representative, registered representative, customer's broker, customer's man
(hypernym) businessperson, bourgeois

The brokerage firm employee who handles stock orders  for clients. See: Broker.

see Account Manager.