Systems Thinking and Lean: Complementary or Competitive Approaches?
by Michael Ballé
What is the relationship between systems thinking and lean? That's a fascinating question, one not so easily answered, because we're talking about two very different approaches, one a philosophy as well as a set of tools, the other, a practice. In its broadest sense, systems thinking is a framework that takes into 
account the interconnected nature of systems. It is also a thinking tool, which helps us look at the impact of feedback loops on how a system behaves; analyze specific situations to explain otherwise puzzling behaviors; and design interventions with an eye for potential unintended consequences.
Lean, on the other hand, is strictly a practice, not a philosophy. It is based on hands-on know how about how to teach people to improve their own processes in terms of both customer satisfaction and cost management by eliminating waste. Taiichi Ohno, a key figure in developing the lean approach, would often say things like: "Don't look with your eyes, look with your feet. Don't think with your head, think with your hands." As a practice-oriented movement, lean is by and large wary of abstract thinking and generalizations.
Nonetheless, although systems thinking and lean operate at these two different levels, I have learned from personal experience that they are complementary and are based on similar insights. An understanding of system thinking dramatically improves the learning curve of lean techniques. Having worked with systems thinking concepts and system dynamics simulations for years before studying lean practices in detail, I immediately saw the purpose (if not the application) of lean, which wasn't the case for my colleagues without a systems thinking background.
Conversely, at the time, I was part of a group tasked with figuring out ways to practically apply systems thinking concepts in day-to-day operations. Although we experimented, we generally floundered. What we did find was that the lean techniques offered a hands-on way to apply systems thinking concepts. Because lean practices have been developed over several decades, an entire field of experience exists in terms of how to make them work.
The bottom line: Without an understanding of systems thinking, it's hard to get lean right, and without the practice of lean techniques, it's difficult to make systems thinking a day-to-day reality to concretely improve system performance.
To Understand and to Change
The rapid progress of science since the Industrial Revolution has been driven by the close interplay of theoretical and practical advances. I believe that the mutual interdependence of systems thinking and lean offers a true opportunity here. By recognizing the synergies between these two fields, we can drastically increase our capacity to improve systems.
The bad news is that integrating these two approaches means more work. If I'm correct, system thinkers must acquire the discipline of lean practice. This has been my own particular path: fun, interesting, but never easy. And lean practitioners must make the effort to understand systems thinking, which is a significant intellectual investment.
Still, I believe this challenge is worthwhile. In today's hypercompetitive markets, companies need the performance improvement promised by lean. Furthermore, the strong systems thinking undercurrent of lean makes it focus on reducing waste of all kinds, including externalities such as pollution and garbage. Since its humble beginnings to its recent 2020 global vision, Toyota has continuously aimed to offer value to society overall. Considering the problems we collectively face in this new century, a proven method of industrial improvement also intent on reducing waste in all its forms should not be dismissed lightly.
One of the enduring puzzles of the lean movement is why it hasn't spread more quickly through industry: Many try, few succeed. Systems thinking, I believe, could contribute significantly to solving this conundrum by providing an overall framework to lean practice. To paraphrase Karl Marx, the point is not merely to understand the world, but to change it. Systems thinking offers the means to understand; lean, the practice to change. By pursuing both jointly, we can learn faster how to change the world in the right way to face our global challenges.
Adapted from "What Is the Relationship Between Systems Thinking and Lean?" published in The Systems Thinker, November 2009, V20N9.
Michael Ballé is associate researcher at Telecom ParisTech and managing partner of ESG Consultants. He has written several books and articles about the links between knowledge and management (Managing with Systems Thinking, The Effective Organization, Les Modèles Mentaux), and more recently, co-authored two business novels, The Gold Mine, which has received the Shingo Prize for Excellence in Manufacturing Research, and The Lean Manager. Michael is co-founder of the Projet Lean Entreprise and the Institut Lean France.
Lock photo by Nancy Daugherty