This paper describes the main functionality and design aspects for the integration between MES and SAP r /3 systems. Massive product types, faster cycle times, smaller inventory buffers, increased customer expectations, less tolerance for errors and heightened competition. More than ever, we need to manage rapid change and reduce costs at the same time. Today, the most promising way to meet these challenges is to increase coordination between enterprise and production systems. Start with existing or optional connectivity capability in our ERP systems such as SAP's XI or xMII or using XML or other standard protocol. Next, we create a functional specification that includes compliance with ISA/ANSI S95, GAMP and other standards, depending on our situation and preferences. Then we create an interface to our plant systems using proven open standard solutions.