Lean methodology explained — eliminating waste to deliver value

Lean methodology is a management approach focused on maximising value to the customer while minimising waste. It originated in Toyota's production system (TPS) and was documented by Womack, Jones and Roos in The Machine That Changed the World (1990).

The five principles

1. Value: define value from the customer's perspective
2. Value stream: map all steps in the process; identify and eliminate non-value-adding steps
3. Flow: ensure value-creating steps flow without interruption
4. Pull: produce only what is needed when it is needed (not in advance)
5. Perfection: continuously improve toward zero waste

The eight wastes (DOWNTIME)

Defects, Overproduction, Waiting, Non-utilised talent, Transportation, Inventory, Motion, Excess processing. In knowledge work, the most common wastes are waiting (for approvals, information), excess processing (over-engineered solutions) and non-utilised talent.