When setting out on the journey to become a Lean organization, companies often miss the true importance of utilizing Value Stream Mapping. Often companies overlook implementing Step Four (Value Stream Mapping product families), as outlined in Chapter 11 of Lean Thinking. This can be a critical mistake in creating a sustainable Lean Initiative.
Value Stream Mapping should be viewed as the backbone of any Lean Initiative and process improvement endeavors. Simply picking trouble areas for improvement without examining the entire value stream of the product family or families utilizing the resource can create undesirable results long term. Value Stream Mapping provides us with the information necessary to understand the actual flow of materials, resources and information through all processes from start to finish for the family of products or services chosen. By obtaining this knowledge, we can see where flow is interrupted and where to start making improvements that increase the flow across the value stream. Simply attacking a troubled area in the process without understanding the true value stream could introduce additional WIP (work in process) and inefficiencies in the processes, thus increasing the process lead time across the overall value stream.
Value Stream Mapping provides us with a tool to start process improvement through a systematic approach. We start by mapping the current state for a particular product family from start to finish usually within the four walls of a facility. From this current state map, we apply Lean tools to create a future state map with an improve process lead time focused on eliminating waste and creating flow across the entire value stream. This future state map dictates where and what type of Kaizen Events (Improvement Events) will be required to meet the future state map objectives. The results of our future state map implementation are evaluated against the performance metric objectives developed for the future state value stream. The future state accomplished through our deployment of Kaizen Events is now our current state for the value stream. A period of evaluation should be performed and the value stream mapping process repeated to create a new future state map. This process could take place several times in the journey to become a World Class Company. Typically value stream mapping plans should be developed with implementation to be completed within (6 -12) months. This process is repeated for all value streams across the organization to achieve world class improvement results. The true value in value stream mapping is the creation of process improvement plans that can be implemented systematically across the company with sustainable results.