A primary objective of ERP is to integrate the various parts of a company. The chapter discusses six levels of enterprise integration and the ability of ERP to satisfy each of them. We analyzed six case studies that included IBM, Cisco, Tecktronic, Vandelay, China Holdings, and APD Manufacturing. We found evidence to support the existence of the six levels of integration. APD and China Holding did not exhibit evidence of global integration while the others did. System-User (Level–II) integration was missing from all except APD. Islands-of-Technology integration is no longer the dominant integration issue it was in the 80’s. The dominant integration issues are functional integration, customer relationship management, and supply chain management.