Lean is the practical application of systems thinking to the improvement of production or productive processes. It combines this thinking with a set of principles, tools and techniques focused on reducing complexity in the production stream. Activities that don’t add value are eliminated. Bottlenecks and other constraints on process flow are likewise taken out of the process to produce a smooth process flow. The result is reduced cycles times, increased inventory turns, simplified and streamlined processes that work faster.
Lean was first defined by James Wolmack and Daniel Jones in their landmark study describing the Toyota Production System (TPS) — themodel for Lean. Since then, Lean has been extended to Lean Enterprise that applies Lean to all areas of organizational functioning from accounting to manufacturing to shipping and from the factory floor to the head office boardroom.
Lean has evolved to become a comprehensive maangement system and philosphy. It is perhaps most easily understood as a rigorous effort at eliminating all forms of waste in the enterprise.