Six Sigma for Pragmatists

Everything and Everyone Can Always Improve

Previous posts to this blog have emphasized the critical importance of competitiveness in today’s global economy. The need to be (and remain) competitive applies to all of the business processes that comprise a business unit. So, methods must be provided to assure that business processes are continuously improved. “Business processes”, as used here, means production processes and “softer” business processes, such as invoicing and purchasing.

An earlier post [1] suggested that two modes of continuous improvement should be pursued simultaneously. One mode consists of a multitude of small improvements achieved from day to day. This mode I compared to a ramp. The other mode is occasional and intended to produce larger changes. This second mode resembles a staircase.

The first mode of continuous improvement — the ramp — might consist of basic continuous improvement methods, such as corrective actions, preventative actions, and internal auditing. The improvement ramp can be significantly augmented by applying Lean Manufacturing techniques.

The second mode — the staircase — proceeds on a project basis, where improvement projects are selected in accord with their urgency and importance to the competitiveness of the business unit as a whole. Six Sigma offers an effective vehicle for achieving larger “staircase” type improvements.

What Six Sigma Is

Dreamstime - Six SigmaSix Sigma consists of a set of statistical tools and processes for applying those tools in order to reduce business process variation. As process variation decreases, quality defects decrease, materials waste is reduced, while throughput and customer satisfaction improve. Similarly, Six Sigma can be applied to energy utilization, environmental emissions and water usage, among other environmental concerns.

Six Sigma requires that practitioners be knowledgeable of and experienced in the application of the Six Sigma statistical tools. Substantial amounts of training are usually required. Fully trained practitioners are certified as “black belts”, while less training is required to earn certification as a “green belt” or a “yellow belt”. Projects are conducted by teams, which are usually led by one or more “black belt”, along with some number “green belts” or “yellow belts”. Generally speaking, “black belt” is a full time assignment, while other “belts” work on Six Sigma teams part time.

Lean and Six Sigma

As mentioned earlier, Lean Manufacturing techniques continuously improve business processes through the reduction and elimination of waste, in all of its nefarious forms. Lean Manufacturing can be combined with Six Sigma. The combined approach, usually referred to as “Lean Six Sigma” or “Lean Sigma”, provides a wealth of tools for improvement, by “ramp” and by “staircase”. Of course, it is necessary to learn to use these tools and to provide a structured approach for their application.

For Smaller Manufacturers

Large companies can dedicate significant numbers of talented people and training resources to Six Sigma. Smaller firms may find it difficult to do likewise, especially in bad economic times.

Lean Manufacturing techniques, on the other hand, are simpler than Six Sigma. Lean Manufacturing utilizes the people who operate the business processes to improve those processes, rather than relying on a cadre of specialists. Further, manufacturers need Lean Manufacturing for its “ramp” improvements. So, investment in Lean training and deployment is, in today’s global economy, almost a given.

Smaller manufacturers may prefer a pragmatic approach. My usual suggestion is to put Lean to work first. Make “ramp” type improvements first. Introduce Kaizen Events [3] as familiarity with Lean Manufacturing techniques grows. The Kaizen Event provides an entry to “staircase” type improvement. Over time, add Six Sigma tools and expand from Events to larger projects that can address larger and broader opportunities for improvement. Grow into Lean Six Sigma.

Thoughtful comments and experience reports are always appreciated. Click on the title of this post to open the comments section.

…  Chuck Harrington

. — When it is time for your firm to seriously pursue Sustainability, contact me — C.H.


Note: This blog and associated website ( are intended as a resource for smaller manufacturers in the pursuit of Sustainability. While editorial focus is on smaller manufacturers, all interested readers are welcome. New blog posts are published on Wednesday evenings.

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Image: Dreamstime

[1] It may be useful to read The Ramp and the Staircase, this blog,


[2] I’m not going to discuss the history of Six Sigma or the details of its methods here. There is plenty of information readily available on the web. Your friends at EPA offer a free 94 page starter at: The American Society for Quality offers discussion, courses, books and more at: Amazon has more books on Six Sigma than I can count.  Google “Six Sigma” and see what happens.


[3] Kaizen Events are focused efforts at improving a specific process. Typically, Kaizen Events last 3 to 5 days. Events must be well planned. The use of an internal or external consultant is advisable, especially initially.