Current Literature - February 2003 - ASQ

Current Literature - February 2003


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Roger Hoerl, manager of the applied statistics lab at General Electric’s global research center



Sooner or later, almost all organizations struggle with the high cost of excess inventory. The natural response, often achieved through lean manufacturing techniques, is to drastically reduce inventory to a bare minimum. This typically produces significant cost and productivity savings, but the organization will soon begin to receive customer complaints about stock-outs and delivery delays, resulting in lost business.

The sales and marketing departments will then demand inventory levels be increased to satisfy customer expectations, and the organization will end up back where it started. Eventually, the finance department will complain about the carrying cost of the high inventory levels, and the organization will repeat the vicious cycle all over again.

Some companies go through this cycle on an annual basis. Fortunately, Six Sigma has the ability to solve this problem once and for all because its statistical methods are well suited to helping an organization account for the variation in customer demand, production and delivery processes. The methods enable a joint optimization of both the low inventory critical to quality characteristics and the high customer availability critical to quality characteristics. Six Sigma’s control plan then ensures the solution is lasting and not dependent on who is currently winning the battle between sales, marketing and finance.

For more details on Six Sigma and supply chain management (SCM), try these books:

Lean Six Sigma: Combining Six Sigma Quality With Lean Production Speed, Michael George, McGraw-Hill, 2002. This is a nice book, even though it focuses more on lean than Six Sigma. I recommend it because it has a chapter on the total supply chain and another on logistics.

Cause and Effect Lean: Lean Operations, Six Sigma and Supply Chain Essentials, John Bicheno, Picsie Books, 2000. This is a quick reference guide that focuses on the supply chain and uses fishbone diagrams to convey its main concepts.

Robert B. Handfield, Bank of America University distinguished professor of supply chain management and director of the Supply Chain Resource Consortium at North Carolina State University



SCM is not, as many believe, a flash in the pan. The economic downturn has been a strong indicator to top management that a new model for managing customers and suppliers is needed. The only thing organizations still need to do is take out cost and work better with their suppliers.

The future competitive channel, however, will not involve organizations. Instead, supply chains will be competing against other supply chains. To succeed in difficult and prosperous economic times, all the organizations that make up an industry’s supply chain need to step on the brakes or on the gas in a collaborative manner.

The winning organizations will then be able to apply Six Sigma principles to projects that involve not only internal operational improvements, but also projects that span their customers’ and suppliers’ processes. The best organizations will share the risks and rewards associated with collaborative process improvement strategies.

The new strategy behind supply chains was described by Jeff Trimmer, former vice president of purchasing at DaimlerChrysler, in terms of three principles:(1)

  1. The only entity that puts money into a supply chain is the end customer.
  2. The only solution that is stable over the long term ensures every element of the supply chain, from raw material to end customer, profits.
  3. SCM is about the economic value and total content of a product or service.

Now it’s up to corporate management to develop a comprehensive plan for redesigning supply chains to meet these criteria. The following books can help managers learn how to apply these principles:

World Class Logistics: The Challenge of Managing Continuous Change, global logistics research team at Michigan State University, Council of Logistics Management, 1995. This book details best practices in logistics collected through detailed interviews and meetings with corporations worldwide. Although the book was printed in 1995, these lessons are still cutting edge and are equally important today.

Powered by Honda: Developing Excellence in the Global Enterprise, David Nelson, Patricia Moody and Rick Mayo, John Wiley & Sons, 1998. This book is a wonderful how-to manual developed by one of the world’s leading experts, Dave Nelson. I interviewed many Honda employees who were involved in supplier development when Nelson was leading the purchasing group, and I was extremely impressed with the approach’s success. The book provides some great insights into how to create win-win kaizen improvement projects with suppliers.

Learning To See, version 1.2, Mike Rother, John Shook, James Womack and Dan Jones, Lean Enterprises Institute, 1999. Even though it centers around the automotive industry, this book is a primer for those wanting to study value streams and identify opportunities for improvement that can deliver cost reductions, cycle time reductions and performance improvements on focused business processes.


  1. Interview on, August 2001.

Six Sigma Bestsellers*

  1. Rath & Strong's Six Sigma Pocket Guide, Rath & Strong, 2000.
  2. Strategic Six Sigma: Best Practices From the Executive Suite, Dick Smith and Jerry Blakeslee, John Wiley & Sons, 2002.
  3. Six Sigma Project Management: A Pocket Guide, Jeffrey N. Lowenthal, ASQ Quality Press, 2002.
  4. Lean Six Sigma, Michael L. George, McGraw-Hill, 2002.
  5. Six Sigma Simplified, Lowell Jay Arthur and Jay Arthur, Life Star, 2000.
  6. Six Sigma for the Shop Floor: A Pocket Guide, Roderick A. Munro, ASQ Quality Press, 2002.
  7. Guiding Successful Six Sigma Projects, Oriel, 2000.
  8. The New Six Sigma: A Leader's Guide, Matt Barney and Tom McCarty, Prentice Hall, 2002.
  9. Six Sigma for Managers, Greg Brue, McGraw-Hill, 2002.
  10. The Six Sigma Book for Healthcare, Robert Barry, Amy Murcko and Clifford Brubaker, Health Administration Press, 2002.

*Compiled using data from, ASQ Quality Press and

Editor's Note

The “Current Literature” department features information about relevant Six Sigma publications and articles that readers will find useful. Please send your recommendations to the editor at

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