CIMdata - Control systems for managing and monitoring work-in-process on a factory floor. MES is used in manufacturing to track and document the processes from raw materials to finished products. MES provides information for manufacturing users in real time or near real time to see current conditions on the plant floor and how to optimize resources (e.g., people, machines, processes).

MES operates across multiple function areas: resource scheduling, order execution, production analysis, equipment availability, quality, material tracking, and exception processing. MES creates the “as-built” record, capturing the BOMs' data, processes, and outcomes of the manufacturing process.

MES’s relationship to PLM is a bidirectional interface with PLM hosting the product definition and version and MES returning the as built definition.

Siemens - Manufacturing Execution Systems (MES) are software solutions that ensure quality and efficiency are built into the manufacturing process and are proactively and systematically enforced.