The process of creating a visual map of the value stream in order to show the flow of materials and information. Value Stream Maps have been widely used as a central component of the Toyota Production System. They include information on takt time (demand rate), inventory levels, changeover times, and manpower.
A Current State map is first constructed to describe the current process. Planned improvements are then incorporated into a Future State map, which guides the improvement actions.
Value Stream Maps are employed on virtually every Six Sigma project during the Define Step of the DMAIC cycle. They are very useful to clarify the mission and get everybody on the same page. At a big-picture level, they may be used to set business level priorities, and they may be used again in greater detail to set individual project priorities. They also may be revised at later phases of the DMAIC process as new information becomes available, or if a finer level of analysis is required.
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