This article intends to answer what manufacturing execution systems (MES) are and describe their relationship with other information systems. It summarizes the features of those significant MESs being used today and discusses their limitations and where they should evolve in order to accommodate customer needs for faster real-time response, the expanded functionality, and increased complexity, as well as computing technologies and research areas that support such evolution. The main message is that it is essential for a semiconductor manufacturer to invest into advanced MESs to keep them competitive in the severely intensified global marketplace. As an MES is deployed on the shop floor in a manufacturing enterprise, the manufacturing process becomes information driven, contributing to both overall productivity and the financial viability of the manufacturing enterprise. Lastly, recognizing that MES deployments are not restricted to the semiconductor industry, the advancements could be applied with little or no refinement to other automated manufacturing environments.