Value Stream Mapping: What is it and how deep should you go?
By Dennis Keay
What is a Value Stream Map (VSM)?
If you haven’t heard of Value Stream Mapping (VSM), in a nutshell, it’s a powerful tool to help you see opportunities to streamline your business processes. Unfortunately, many people make it sound much more complex than it need be, and think that you need to be an expert to use it. It’s no more complex than driving a car—and most of us can do that. Of course, you can make it as complex and daunting as you wish, but that defeats the purpose! The terminology or ‘jargon’ associated with it can also make it sound a bit complex and can put people off. So, let’s look at the fundamentals and demystify it.
A VSM is a schematic drawing or ‘block-diagram’ of a process flow. It visually represents the sequence of steps or activities within a process, together with the time it takes to perform those steps. It also shows queuing time or wait-times between process steps. It does NOT show the physical layout of the process.
Drawing and reading a VSM is a bit like drawing or reading a road map, in that on a road map there are symbols for traffic lights, railway crossings, bridges and so on. Once you know what the symbols mean, you can make sense of the map. Value stream mapping uses its own set of symbols.
Some road map symbols
(Courtesy Melway Publishing)
Some Value stream mapping symbols
If people want to drive from place A to place B where they haven’t been before, instead of guessing, they usually use a map of some sort to find the most efficient way. The VSM is a tool to help get you from where you are in business to where you want to be. But, because people don’t know about it, or because they think it’s very complex, they often avoid learning about them or using them till some time well into the future. When they do that they can waste valuable time and opportunity, without even realising ‘there’s a better way’.
Why is it called a Value Stream Map?
Well, the ‘stream’ bit is pretty self-explanatory, because we can associate a stream with flow. Flow of value in this case. But what about ‘Value’. In general, Value is defined as something your customer is happy to exchange money for. It’s value from their perspective.
I don’t want to go into too much detail here, but below is a sample of what a pared-down Value Stream Map might look like. (They do normally contain more detail to give more information about the process—for example, the number of operators at a workstation, etc.)
It might look confusing if you don’t know what the symbols mean and haven’t had a lesson in how to read it, but don’t let that delay you from learning.
Here are some key points worth noting:
- Remember, the VSM is just a tool to help you identify and prioritise improvement opportunities. After you make improvements your map WILL change. That’s the whole point! So don’t spend too much time trying to get your map perfect. Even if you did get it ‘perfect’, it would soon become outdated as you make changes.
In fact, value-stream-mapping is an iterative process. You start off by creating a ‘current state map’, and with the improvement opportunities you identify, you can forecast what the map should look like after you’ve implemented those improvements. That forecast is called a ‘future state map’. Then, after the first round of improvements are made, you gather new data about your improved process and create a new ‘current state map’ and identify the next opportunities for improvement.
You’ll get more clarity and accuracy each time you iterate the map, and, like driving a car, it becomes easier with practice.
- A value-stream map is a ‘snapshot’ of the overall process at a given point in time. There can be significant variation from day to day, week to week, or month to month. Sometimes work-in-progress may have to queue for long periods between process steps, and other times not queue for long at all. (Similar to when you go to the supermarket checkout, or the bank.) A large part of what we’re trying to do with the improvements is to reduce variation and make the overall process more stable, predictable, and flow smoother and faster.
- The mapping process is best done as a team based exercise with people who work in different parts of the process. It’s amazing what a great team-engagement and communication tool the mapping exercise can be, which is a great benefit in itself.
- You can buy software for value-stream mapping, but in my view it’s generally not necessary. You’re better off using a white board or sheets of paper and post-it notes on a wall, where people can get involved as a team, move or add post-it notes and quickly build the map. It’s dynamic and can be fun!
Software versions do have their place, but I find that they’re best used to document the process after you’ve mapped it out, so that the map can be stored for future use or shared with people remotely, and can be particularly useful when a company has a number of different sites around the country, where those sites have essentially the same type of processes. That way they can get shared learnings.
- I’m often asked: “We’ve got lots of products and value streams in our business, so do we have to make lots of maps or a map for each process?” My answer is usually: “Let’s keep it simple. There’s normally a lot of commonality between your various maps, for example, the way goods, materials and services are ordered, received, stored, transported internally, dispatched, invoiced, and so on. Often, when making improvements on one key process it will automatically have a beneficial impact on other processes / maps. So, pick a key process and get started.”
- There are several tools we use to identify improvement opportunities. The VSM is just one of them! It’s a powerful tool, but not always needed. Just because you have a hammer doesn’t mean you use it when a screw-driver is appropriate. So, I’m not advocating using it just for the sake of using it. Using the right tool for the job always makes the job easier, and VSM is a really good one to have in your toolbox. Without knowing about it and understanding how it’s used, would be like a trades-person having a pair of pliers to undo nuts and bolts, without knowing that there are socket sets and ratchet spanners that could make life so much easier.
If you’re not familiar with VSM, take some baby steps to add this powerful tool to your business improvement toolbox. Again, let me emphasis, don’t try to get it perfect, only go as deep as you need to go to make substantial improvements to your processes, and don’t let ‘perfect’ become the enemy of ‘good’. After all, the aim of the game is to improve your processes, not to make pretty maps! Go have some fun and get business done!