This is the 6th edition of a book that has become a standard reference to Lean principles, systems, and tools. It is used by Lean practitioners and Industrial Engineers in the UK, USA, Ireland, Scandinavia, South Africa, and Australia. Like earlier editions, the book is written in plain language, with minimal padding, especially for busy practitioners and managers at all levels. Previous editions have sold over 130,000 copies, and adapted versions have been translated into Danish, Chinese and German. Across its editions, the Lean Toolbox has been prescribed reading at several UK, US, Irish and South African universities, and has featured as a standard reference for the APICS / ASCM professional CPIM examination. This edition marks once again a significant update. New sections now cover digital tools and how these can support lean transformations, how to respond to complexity and uncertainty in the world firms operate in, and the importance of psychological safety in making sustainable