Introduction to process mapping in Six Sigma

Process mapping found a natural place within the Six Sigma frameworks – both DMAIC (Define, Measure, Analyze, Improve, Control) and DMADV (Define, Measure, Analyze, Design, Validate).

• DMAIC is aimed at understanding a business’s existing process. Process mapping can help measure and analyze how an organization delivers a service or operation, by reconstructing each process step involved and therefore the root causes of any issues.
• DMADV helps with creating new processes. Process mapping gives a business an idea of the requirements of a certain function or operation, from which to design an optimal process for delivering the business goal.

So that’s the theory. Now for a practical look at process mapping in Six Sigma, and how it can be used in businesses.

What is process mapping in Six Sigma and how does it work?

Six Sigma process mapping is similar to standard process mapping, but involves an element of triaging. That’s because it comes on the back of a business problem or area that’s been scoped out at the start of the Six Sigma process improvement initiative. So while process mapping will give you a visual representation, Six Sigma encourages businesses to interrogate it by looking for steps and activities that don’t add value. Businesses will also typically compare their current process map against a potential new one.

As with conventional process mapping, there are different types of process maps in Six Sigma, including:

• Value stream map: A detailed process map lays out all the people and tasks involved in delivering a product or service to a customer. Value stream mapping is particularly pertinent to Lean Six Sigma methodology – the offshoot approach focused on eliminating waste and redundant processes. Anything that’s not directly and essentially contributing to the fulfillment process flow is marked for action.
• Control chart: This type looks distinct from other process maps as it doesn’t display steps and blocks of information, but plots process variation or quality management data. Each process output is marked above or below a central baseline, reflecting fluctuations and deviations. The idea is to gauge how consistent and stable a process is, and therefore whether optimization and compliance measures are required.
• Swimlane diagram or cross-functional diagram: Useful for the process improvement aspect of Six Sigma, mapping out the different departments and functions involved across an entire process can show where teams and dependencies need to work seamlessly together. This is why a swimlane diagram is sometimes called an opportunity flowchart.
• SIPOC diagram or SIPOC map: Breaking down a function into suppliers, inputs, process, outputs and customers using a relationship map brings focus to operational delivery, and therefore guides analysts towards areas or bottlenecks that aren’t contributing value.

Many of these types of process maps are templated in Microsoft Visio, so you’ll often see it referenced as one of the most common Six Sigma process mapping tools.

What are the benefits of process mapping in Six Sigma?

Six Sigma helps guide process mapping projects towards transparency over business operations and uncovering improvement opportunities. Process mapping can provide a foundation for root cause analysis – itself a component of Six Sigma methods – by spotting bottlenecks and disconnects that can be targeted. It also enables lean methodologies by providing a picture you can use to more clearly identify and then remove redundant, duplicated, or overly complicated steps and processes.

The process mapping method itself is relatively accessible for anyone in the business to take on. It just involves gathering input from stakeholders – whether that be interviewing them, sending out a survey, or holding a group workshop – and then organizing the insights into a diagram. This makes it an appealingly straightforward exercise – or so it seems.

What are the limitations of process mapping in Six Sigma?

Don’t be deceived by the apparent simplicity of Six Sigma process mapping, as there are a fair few catches to consider.

First, there’s the resource requirement. Stakeholder input sessions can easily build up into a time-consuming project management slog, especially if you can’t find a time when everyone is available. The sessions themselves can also break out into blame-finding and finger-pointing when teams get defensive about responsibility, which it falls to valiant analysts to moderate. And the manual effort doesn’t end there, as analysts are required to collate and rationalize all the (probably conflicting) information, from different sources.

Then there’s the resulting Six Sigma process map itself: subjective, static, and incomplete or inaccurate, since it’s based on stakeholder opinions, impressions, and best guesses at that one point in time.