The history of Kaizen, Lean and the Toyota Production System

When did Kaizen and Lean begin? A timeline

There is no single founding date. The ideas were assembled over about eighty years, in Japan and the United States, and were named long after they were in use.

1. 1896 Sakichi Toyoda develops a power loom with a device that stops it automatically when the weft thread breaks. Toyota traces jidoka, stopping the work when something is wrong, to Sakichi Toyoda's looms. [1]
2. 1913 At Highland Park, Michigan, Henry Ford combines interchangeable parts, standard work and moving conveyance into what he called flow production. [6]
3. 1924 Sakichi Toyoda's Type-G automatic loom changes its shuttle without stopping. In the same year, at Western Electric, Walter Shewhart draws what is now recognised as a control chart in a one-page memorandum dated 16 May. [1][35]
4. 1933 to 1937 Toyoda Automatic Loom Works sets up an automobile division on 1 September 1933. Toyota Motor Co., Ltd. is established on 28 August 1937, with Risaburo Toyoda as president and Kiichiro Toyoda as vice president. Toyota names Kiichiro as its founder and as the man who argued for making parts just in time. [1][5]
5. 1939 Shewhart's book Statistical Method from the Viewpoint of Quality Control, edited by W. Edwards Deming, presents specification, production and inspection as a circle and compares it to the scientific method. [11]
6. 1940 to 1945 The United States runs the Training Within Industry service, whose courses for supervisors include Job Instruction, Job Methods and Job Relations. [25]
7. 1943 Taiichi Ohno, who had joined Toyoda Spinning in 1932, moves to Toyota Motor, where Wikipedia has him start as a shop-floor supervisor in engine manufacturing. [15][33]
8. Late 1940s to early 1950s The foundations of the Toyota Production System are established by trial and error at Toyota's Honsha machinery plant. Toyota studies how supermarkets restock their shelves, and in 1953 applies that logic in its main plant machine shop: the origin of kanban. [2][27]
9. 1949 Toyota introduces statistical quality control. [3]
10. 1950 In the summer, at the invitation of the Union of Japanese Scientists and Engineers (JUSE), Deming teaches statistical quality control to engineers and managers in an eight-day course in Tokyo, and shows a four-step wheel of design, production, sales and research. He gives the royalties from the printed lectures to JUSE, which uses them to fund the Deming Prize. [11][12][36]
11. 1951 The four steps appear in Japan as plan, do, check, act. In May, Toyota launches its Creative Idea Suggestion System. JUSE's history of the Deming Prize lists the prize as established this year, with the first award ceremony on 22 September; Wikipedia dates the board's decision to December 1950. [3][11][13][36]
12. 1955 Shigeo Shingo, an outside consultant, begins teaching industrial engineering courses at Toyota. [34]
13. 1960 Toyota begins implementing its production system at all of its plants; by the late 1960s it is being introduced at the companies that supply it. [2]
14. 1961 to 1965 Toyota introduces total quality control in June 1961 and launches the meetings that became its quality circles in November 1962, the year Kaoru Ishikawa and JUSE introduce quality circles. Toyota is awarded the Deming Application Prize in November 1965. [3][37]
15. 1977 Sugimori, Kusunoki, Cho and Uchikawa publish an account of the Toyota Production System and kanban in English, in the International Journal of Production Research. [19]
16. 1978 Ohno's book on the Toyota Production System appears in Japan in May. The English edition follows in 1988. [15]
17. 1980 The American television documentary If Japan Can... Why Can't We? brings Deming to the attention of managers in the United States. [36]
18. 1984 NUMMI, a car plant in Fremont, California, owned jointly by General Motors and Toyota, has built its first car by December. [30]
19. 1985 to 1986 Masaaki Imai founds Kaizen Institute in Switzerland in 1985 and publishes Kaizen: The Key to Japan's Competitive Success in 1986. Deming's Out of the Crisis takes that title in 1986. [14][36][38]
20. 1988 John Krafcik's article Triumph of the Lean Production System, in Sloan Management Review, uses the word lean for a production system. Utah State University creates the Shingo Prize. [18][19][34]
21. 1990 The Machine That Changed the World, by James Womack, Daniel Jones and Daniel Roos, reports a five-year study at the Massachusetts Institute of Technology and makes the term lean production widely known. [6][23]
22. 1996 to 1997 Womack and Jones publish Lean Thinking in 1996, reducing Lean to five principles. Womack founds the Lean Enterprise Institute in 1997. [6][7]
23. 2001 Toyota writes down the values it had passed on by practice as the Toyota Way 2001, resting on two pillars: continuous improvement and respect for people. [4]
24. 2003 to 2004 Books carry the methods into administrative work: Value Stream Management for the Lean Office in 2003 and The Complete Lean Enterprise in 2004. Jeffrey Liker's The Toyota Way is published in 2004. [16][17][22]

The books named in the timeline are described in the Lean and Kaizen reading list.

Who were the people behind Kaizen and Lean?

Which origin stories are disputed?

Several things that are usually stated as fact are attributions made later, or are told differently by different sources. These are the ones a careful writer should qualify.

Does kaizen mean continuous improvement?

Not literally. Wikipedia's article on Kaizen says the Japanese word means improvement or change for the better, with no built-in sense of continuous or of a philosophy; that sense was added by its use in business, at Toyota above all. The Lean Enterprise Institute's lexicon, like most management writing, defines kaizen as continuous improvement. Both are right about different things: one about the word, the other about the practice. [9][24]

Is Kaizen a Japanese idea or an American one?

Both, depending on the source. Wikipedia's article on Kaizen says the small-step approach was developed in the United States under the wartime programme Training Within Industry, which taught people to examine their own jobs and suggest improvements, and that the programme was installed in Japan in 1951, under the occupation; its article on the programme adds that the first Japanese were trained in it about 1947, in India. Kaizen Institute, the firm Masaaki Imai founded, also gives the programme a key part in the creation of Kaizen. Toyota's own account of its production system starts with the Toyoda family's looms and does not mention the programme. What is not in dispute is that the practice was developed into a company-wide habit in Japan. [1][14][24][25]

Who invented the 5 Whys?

It is usually credited to Sakichi Toyoda: Wikipedia's article on the five whys says he originally developed it, although the same article opens by saying the technique was described by Taiichi Ohno. The written source is Ohno, whose book describes asking why five times and gives the example of a stopped machine traced back to a missing strainer; the Lean Enterprise Institute's lexicon credits the description to Ohno and cites that book. The safest statement is that Ohno described it in writing; none of the sources we opened shows where the credit to Sakichi Toyoda comes from. The practice itself is taught in the lesson 5 Whys examples from office work. [10][26]

Who created PDCA?

No one person. Ronald Moen's history, published by the Deming Institute, traces it in steps: Shewhart's three-step circle of 1939, the four-step wheel Deming showed in Japan in 1950, and the plan-do-check-act wording that appeared in Japan in 1951, a step Moen takes from Masaaki Imai's account and for which nobody claimed authorship. PDCA is often called the Deming cycle, but Deming did not accept it: in a 1990 letter Moen quotes, he called PDCA a corruption, and he published plan-do-study-act as his own version in 1993. How to run the cycle is in the lesson on the PDCA cycle. [11]

Did Shigeo Shingo invent the Toyota Production System?

No, although it is often said. Wikipedia's article on Shingo calls this a myth: he taught at Toyota as an outside consultant and documented the system, which was created inside Toyota by Ohno and others. Toyota's own account names Sakichi, Kiichiro and Eiji Toyoda and Taiichi Ohno, and does not name Shingo. [1][34]

Who defined the seven wastes, and who added the eighth?

The seven are Taiichi Ohno's in the Lean Enterprise Institute's lexicon and in Wikipedia's articles on Ohno and on muda, the second of which cites his book. Wikipedia's article on Lean manufacturing credits the list to Shigeo Shingo instead and calls him a Toyota engineer, which its own article on Shingo contradicts: he was an outside consultant. We follow the Lean Enterprise Institute. The eighth, people's unused skills, has no agreed author: one Wikipedia article says only that later contributors added it, and another cites Jeffrey Liker's The Toyota Way of 2004 for it. Our guide to the 8 wastes in office work uses eight because the eighth is common in offices, not because Toyota listed it. [8][19][31][33][34]

When was the Toyota Production System created?

Over decades, so any single year is a simplification. Wikipedia's article gives one founding year, 1948. Toyota's own chronology says the foundations were laid in one plant in the late 1940s and early 1950s, that all plants began implementing the system in 1960, and that suppliers followed from the late 1960s. [2][21]

Is Lean the same thing as the Toyota Production System?

Lean is a description of the Toyota Production System made from outside, by researchers, in 1988 and 1990, and then generalised into five principles in 1996. Toyota calls its own system the Toyota Production System and describes it through two pillars, jidoka and just-in-time. The two overlap heavily but are not one text: Lean is what others learned from Toyota, written for use anywhere. [1][6][19]

How did these ideas reach office work?

Late, and mostly through books. The first accounts were all about car plants. Books applying the same methods to administrative work followed in the early 2000s, among them Value Stream Management for the Lean Office in 2003 and The Complete Lean Enterprise in 2004. In software, Wikipedia traces kanban for knowledge work from a 2004 project at Microsoft, run on a related method, to a 2006 to 2007 project at Corbis, where the kanban method took shape, and then to David Anderson's book on it in 2010. [16][17][28]

The translation is not automatic. In an office the work is hard to see, the customer is often a colleague, and the waste is waiting more than scrap. That is the subject of the free course, starting with Kaizen in the office, and of the Lean methods reference, which says for each method how it applies to office work and when it does not. Short definitions of the terms used on this page are in the Kaizen glossary.

Try it on your own work

Pick one task that wastes your team's time every week. Describe it in a sentence; KaizenProof names the waste, asks why until you reach the cause, and writes the fix. No account is needed to start.