To more flexibly and easily provide a customizable control system and constructing method therefor, in the control system composed of plural common objects.

A first OCX (object liking and embedding custom control) 10 to be the instance of a common object is provided with an interface 12 transmitting an event and an interface 13 receiving the event, in addition to an interface providing property and methods. The address of the interface 13 of the first OCX 10 is passed to the interface 12 of a second OCX 11 by an interface object 15 and the connection on the event is formed. Thus, the bi-directional communication between the OCX 10 and 11 becomes possible, the function of the second OCX is made the full use from the first OCX 10 and a system which is capable of obtaining a quick response can be constructed.