In the actual development of Information Systems，DSS can only support the selection st ge，not the other two stages which are inseparable from the whole decision—making process．i．e．the intelligence collection stage and the solution design stage．In this paper，the possible methods in which ES can be integrated with DSS，EIS and ESS are analyzed．In view of that different types of application systems can afford different supports for three stages of decision—making process，and that there are some logical relations 0f data proces among those systems，the application systems are reclasified，and the application systems integration framework in support of the high—level management decision and in suppo rt of the whole decision—making process is proposed．