Three Ways to Draw Future State Value Stream Maps

A value stream map is a diagram showing the flow of the material, goods or services and also the supporting information flow. It is typically drawn in a clockwise fashion beginning at the customer in the two o’clock position, backwards through the material and information flow until a complete circle is made from customer request to fulfillment of that request. The current state represents today’s reality as observed and documented by people. The whole point of the mapping exercise is to build consensus on the problems and what needs to be done so the organization can take action.

The future state map is created to show us the way to go. There are at least three ways to draw future state value stream maps.

1. The “begin with the end” approach. One way to draw the future state value stream map is to envision the ideal state and work your way back to an interim implementation time line such as 6 or 12 months. While this is fast and powerful, it requires that you have a clear vision of the ideal or “what good looks like” based on a model of process excellence such as TPS. Or if you are really creative and can think outside the box, a flash of insight may deliver the process innovation. Perhaps the greatest risk with this approach is that smart people are good at fooling themselves into thinking they know the answer. They fall in love with their future state and spend less time studying the current state and its flaws when compared to any ideal.

2. The incremental approach. A second way is to systematically identify and eliminate waste from the current state map, and a new “current state” with less waste your future state. This could include bringing processes closer together, reducing error rates or inventories. This is somewhat tactical and moves your towards the ideal condition step by step, unless you stop seeing the waste. This method requires that you get smarter or sharper in your observation as your current state improves over time. Many have bought the books and employed IEs to faithfully apply the tools, only to get stuck at some point because a vision was lacking. Maintaining a strong customer focus and studying lean systems and solutions will help this approach succeed.

3. The cookbook approach. Ask the “10 questions” for building a future state by applying the lean tools based on a recommended method. The questions vary and the number 10 is arbitrary. The questions typically address takt time / pacemaker, continuous flow, kanban / pull signal / supermarkets, heijunka / leveling, scheduling point, standard work / work balancing, lot size reduction / SMED, build to order vs. build to stock and 3P / product & process design approach. We have seen anywhere from 7 to 12 questions, and in each case the approach tends to be somewhat prescriptive, or fit to the worldview of a particular consultant or leaning organization’s lean implementation standard. If this approach is used, it needs to be customized for whatever type of industry or business you are in. Perhaps the biggest weakness is that this approach rarely if ever identifies organizational, leadership or foundational behavior issues that are causing the current state to be as bad as it is.

The zeroth way. Draw no future state map at all. A detailed current state map completed with plenty of data based on go see gathering is better than a premature future state map built around a little education and a lot of excitement. A few change loops defining where to start and what to do next may be just as good as a future state map.

The most important part of value stream mapping is the kaizen activity that follows it, based on the PDCA cycle.

5 Comments

  1. John Santomer

    July 20, 2008 - 11:25 pm

    It was really informative Jon. It may be confused though, I take it that this is the follow through on a stuck A3 Strategy Sheet? Is this a detailed approach on alternative steps to address the current “botched” situation?
    The PDCA cycle has always been incorporated in the A3 Strategy Sheets as part of the complete cycle of any project after defining the project’s aim/s, responsible ownerships and setting the corresponding time tables for completion.Do you still need this if the A3 Strategy Sheet is covering the whole cycle of the project and is proceeding as planned and approved by the stakeholders?

  2. Jon Miller

    July 22, 2008 - 12:43 pm

    Hi John,
    Most of lean world does not use the A3 sheet yet, but value stream mapping by itself is very popular. So to answer your question directly, “no”.
    Value stream mapping is often a team activity preceding or as part of a kaizen, taking 1-5 days or more on a big sheet of paper, collecting data and “grasping the situation”. It can certainly be a tool that is used as part of the A3 process. Actions that result from VSM should follow PDCA.
    But most users of VSM do not incorporate it into the A3 process, as yet.

  3. Mike

    July 23, 2008 - 12:27 pm

    I see VSM and A3 as different systems entirely. VSM should be, I believe, the first step in understanding how things really are in your plant (or other business entity), how it will look in your “ideal” state, and where you should use specific tools to improve the flow. A “map” shows where the flow stops and that is where our energy should be put. The map allows us to really see what is going on as a whole and how each part relates to the others. It is a vital process, but comes before any A3 strategy or kaizen plan. The current prevalence of conducting a mapping exercise just prior to a kaizen event defeats the entire purpose of the map. The map should be THE MAP–directing our lean journey.

  4. Thomas

    September 1, 2008 - 6:49 am

    Ok, but what do you do when one machine is shared by several product families ?
    It looks fine, because the takt time is for instance 15 min/piece, and the machine cycle time is 5 min/piece. But in fact the machine is not available 100% for this product family…

  5. Jon Miller

    September 1, 2008 - 7:10 am

    If a machine is shared by more than one product family, and a product family is defined as a value stream (as opposed to a value stream that contains several product families for whatever reason) then this will most likely be shown with a supermarket or inventory stock point after the process. This inventory represents the build-up of stock of one product family, to maintain supply during the time when the other type is being produced.
    There would also be a changeover time indicated in the data box, the number of shifts the machine is operated and even the percentage of available capacity can be shown.
    Once it is clearly established that a machine is shared between multiple products, the takt time for that machine is calculated separately based on the net available time divided by the total customer demand for all product families. So long as the average weighted cycle time is lower than the takt time for all product families, there should be no problems. But in fact it is best to fill out what is called a Table of Production Capacity by Process (or Process Capacity Table) to figure out if you have enough capacity.
    Changeover times will need to be deducted from available times, based on the frequency of changeovers per shift. In fact Overall Equipment Effectiveness (OEE) should be taken into account if it is measured for that machine when calculating takt time.
    Note that even if machines in a value stream serve only one product family, the available time (number of shifts operated) may be different, so it is important to ask these questions and do the takt time calculation per each process.