The story of Lean is far more older than the 6 sigma. Thus, from the 15th century, the construction of Venetian boats followed a process rationalized with the introduction of assembly lines for the production.
If Fordism launched the modern bases of Lean (cell organization, modernization of machines...), it is therefore Toyota which, in the 60's, will be the instigator of the Lean philosophy by gathering the concepts of takt time, continuous flow and flexibility.
In the 70's, Toyota industrialized and "systematized" its Lean concept via the "Toyota Productive System" (TPS). It is a philosophical and practical approach whose aim is to increase productivity while eliminating wastes at every level of the factory, the provider and the final customer.
From the 80's, the Just In Time concept, invented by Toyota in the 50's started to develop in big westerm companies.
The Lean philosophy appears then as a way of progress for all the western manufacturers and generalized afterwards. The Lean Manufacturing became one of the basic principle for every company in the world.
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