Client server communication system and method

An information terminal 110, connected to one of a cluster 140 of collaboration servers 142-146 which are allocated by a dispatcher 120, is connected to another information terminal 170-174 via its allocated server. When a customer's web-browser 111 is connected to, say, server 142 by the dispatcher, a button for requesting connection to an agent is displayed. When the customer clicks this button, a customer ID and an IP address of the server 142 are stored in a table 155. After a Computer Telephony Integration server 163 allocates an agent, an agent proxy 173 obtains the stored IP address corresponding to the customer and accesses the server 142. If a customer's own telephone number is also stored, the customer can receive a call back from the agent. The customer can choose as communication means with the agent either a normal external telephone, an internet phone, or chat, (conversational hypertext) and receives a call back by the chosen communication means. The skill group of the agent can be also selected.