Value stream mapping is a cornerstone of the Lean process improvement methodology, and also is a recognized tool used in Six Sigma. A value stream map illustrates the flow of materials and information as a product or service moves through a process. Creating a “current state” value stream map can help you identify waste and also makes it easier to envision an improved state for process in the future.
You can use value stream mapping to improve any process. But unless you use the tool properly, your value stream map may not capture all of the opportunities you have to improve quality and efficiency.
Here are five guidelines to getting the most benefit from the energy you put into value stream mapping:
- Base the Value Stream Map process on customer requirements.
You must understand what the customer values, and use that as your starting point. If you don’t, you risk, in the words of my favorite band The Fall, paying “the highest attention to the wrong detail.”
- Capture the process as it operates now, not how it’s supposed to operate.
A process that worked well when you had 20 employees may not perform as efficiently now that the business is a 200-person company. Be sure you map the process as it happens now, not the way it used to work—or how you wish it worked!
- Assign a Value Stream Map manager to lead the mapping effort.
Input from team members and stakeholders is important, but appoint (or elect) one team member to draw the entire value stream map. This ensures that the manager understands the material and information flows.
- Walk through the process to ensure that the flow of materials and information is accurate.
Make sure your map reflects the reality of the process—verifying this by following the process from start to finish can reveal crucial details you might have missed.
- Focus on one small step at a time. Make sure you capture each step accurately. For example, don’t trust the clock on the wall to measure cycle times—use a stopwatch.
Creating a value stream map of the current state of your process helps you focus on areas of waste such as excess inventory, non-value-added time, and multiple operators. As you envision the future state of your process, you can vary data on the current state map to explore the effects of possible improvements.
While it’s possible to do value stream mapping on paper, software tools like those in Companion by Minitab make value stream mapping a lot easier.
If you've done value stream mapping, what tips do you have to share?