For providing more convenient service to customers on the Internet-based shopping malls, the human assistance can be necessary as well as automated information service. Call centers are typically human based service systems. However, the services of existing PSTN-based call centers are not enough to meet the needs of customers on the Internet because most of them have been designed without considering the interaction with cyber-shopping mall. In this research, we design a call center, which can be well integrated with an Internet shopping mall. It is named as IMC to imply Internet-Based Multimedia Call Center and it contains two parts: Internet Multimedia Dialogue System and Human Agent Assisting System. Internet Multimedia Dialogue System can be thought of an Internet/multimedia version of the Interactive Voice Response (IVR) service of PSTN-based call centers in the meaning that it provides both the multimedia web page and voice through Internet. Human Agent Assisting System aims to supporting the human agents of the call center in providing high-quality individualized information to each customer. Its processes is composed of agent group selection, agent selection, customer information screen pop, web page pop, initiative control, Internet phone connection, and call passing.