Toyota is the world’s most profitable automaker. Its “secret weapon” is lean production — the revolutionary approach to business processes that it invented in the 1950s. Today, businesses around the world are trying to emulate Toyota’s remarkable success by working to implement the company’s radical system for speeding up business and service processes, reducing waste, and improving quality. To help other companies learn to continually improve on what they do, Professor of Industrial and Operations Engineering at the University of Michigan Dr. Jeffrey K. Liker describes the results of his year-long research into Toyota.