Abstract: A call center system includes a CTI server (1) for transferring a telephone call from a customer telephone (2) to reception terminals (31 to 32) of operators, and a customer information database (4) that stores respective telephone numbers of customers, information regarding responses to inquiries from the customers in the past, etc. In response to reception of a call from a customer telephone (2), the CTI server (1) acquires a telephone number of the customer telephone (2) using an originating number notifying service provided by a telephone network, refers to the customer information database (4) according to the acquired telephone number, and preferentially transfers the call to a reception terminal (31) of an operator that has attended to the customer.